Strom is a family tree that runs right in the browser: no account, no server, free of charge. The family tree stays on the device, and a copy in a file keeps it safe. On a computer, ancestor research can be added: with an agent it searches registers and archives, without one it is free and nothing leaves the computer.
After the first visit, it works without internet too.
All content of the site is further down; the guides only show the way.
All steps by combination:
Strom runs at stromapp.info/run/. Nothing gets installed and no account is needed.
https://stromapp.info/run/Done when the screen shows “Welcome to Strom” with the “Add first person” button and the “I have data elsewhere (GEDCOM from MyHeritage, Ancestry…)” link.
Strom can be installed as an app with an icon on the desktop. It is more convenient, but the data is the same as in the browser tab.
The Install button on the right of the address bar → confirm Install
Otherwise: ⋮ → Cast, save, and share → Install…
Neither the button nor the icon in sight? A private window or a guest profile does not allow installing.
Done when the screen shows Strom in its own window and an icon on the desktop or in the Dock.
The first person, then their parents and children. For example Anna Nováková, *1880.
Add first person
Done when the screen shows the card “Anna Nováková” in the tree.
A GEDCOM file from MyHeritage, Geni or Ancestry opens in Strom as a family tree, on a computer and on a phone.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From GEDCOM → choose the file → Insert into tree
On a computer, the .ged file can also be dragged onto the window.
Strom does not open a zip: a file from Ancestry needs unpacking first.
Done when the screen shows a summary (number of people, relationships, photos) and, after confirming, the family tree.
A Strom backup file (.json) opens on any device.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From JSON → choose the file
On a computer, the file can also be dragged onto the window.
Chrome and Edge: the same dialog has “Open from file…”, which links the tree with the file straight away (the next Ctrl+S saves into it). Safari and Firefox only import the file as a copy.
An encrypted file asks for its password when opened; a forgotten password cannot be recovered.
Done when the screen shows the family tree from the file.
The only reliable copy is a file. Each save downloads a new .json file; in Chrome and Edge, the tree can be linked to one file and saved into it every time.
Ctrl + S (Mac ⌘ + S), or Actions (on a narrower screen ⋯) → Export… → Data backup (JSON)
Without a link, every save downloads a new file <tree name>.json to Downloads.
Linking, optional: Actions → Export… → Link to a file on disk… → choose a place. From then on Ctrl+S saves into that file, by hand, not by itself.
Done when the screen shows “Saved to file” for a moment and the .json file in Downloads or in the chosen folder. “Only in browser” returns with the next change.
Next time, Strom opens the same way: same browser and same address, or the icon. On another device, only the file.
Strom is empty? The family tree is usually somewhere else →
Save to a file after every larger change.
Strom runs at stromapp.info/run/. Nothing gets installed and no account is needed.
https://stromapp.info/run/Done when the screen shows “Welcome to Strom” with the “Add first person” button and the “I have data elsewhere (GEDCOM from MyHeritage, Ancestry…)” link.
Strom can be installed as an app with an icon on the desktop. It is more convenient, but the data is the same as in the browser tab.
The app icon on the right of the address bar
Otherwise: ⋯ → Apps → Install this site as an app
Neither the button nor the icon in sight? A private window or a guest profile does not allow installing.
Done when the screen shows Strom in its own window and an icon on the desktop or in the Dock.
The first person, then their parents and children. For example Anna Nováková, *1880.
Add first person
Done when the screen shows the card “Anna Nováková” in the tree.
A GEDCOM file from MyHeritage, Geni or Ancestry opens in Strom as a family tree, on a computer and on a phone.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From GEDCOM → choose the file → Insert into tree
On a computer, the .ged file can also be dragged onto the window.
Strom does not open a zip: a file from Ancestry needs unpacking first.
Done when the screen shows a summary (number of people, relationships, photos) and, after confirming, the family tree.
A Strom backup file (.json) opens on any device.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From JSON → choose the file
On a computer, the file can also be dragged onto the window.
Chrome and Edge: the same dialog has “Open from file…”, which links the tree with the file straight away (the next Ctrl+S saves into it). Safari and Firefox only import the file as a copy.
An encrypted file asks for its password when opened; a forgotten password cannot be recovered.
Done when the screen shows the family tree from the file.
The only reliable copy is a file. Each save downloads a new .json file; in Chrome and Edge, the tree can be linked to one file and saved into it every time.
Ctrl + S (Mac ⌘ + S), or Actions (on a narrower screen ⋯) → Export… → Data backup (JSON)
Without a link, every save downloads a new file <tree name>.json to Downloads.
Linking, optional: Actions → Export… → Link to a file on disk… → choose a place. From then on Ctrl+S saves into that file, by hand, not by itself.
Done when the screen shows “Saved to file” for a moment and the .json file in Downloads or in the chosen folder. “Only in browser” returns with the next change.
Next time, Strom opens the same way: same browser and same address, or the icon. On another device, only the file.
Strom is empty? The family tree is usually somewhere else →
Save to a file after every larger change.
Strom runs at stromapp.info/run/. Nothing gets installed and no account is needed.
https://stromapp.info/run/Done when the screen shows “Welcome to Strom” with the “Add first person” button and the “I have data elsewhere (GEDCOM from MyHeritage, Ancestry…)” link.
A bookmark is enough for an easy return. Firefox on a Mac cannot install Strom as an app.
Ctrl + D (Mac ⌘ + D)
Firefox on Windows can pin Strom to the taskbar with an icon in the address bar. The data stays in Firefox.
Done when the screen shows Strom in the bookmarks.
The first person, then their parents and children. For example Anna Nováková, *1880.
Add first person
Done when the screen shows the card “Anna Nováková” in the tree.
A GEDCOM file from MyHeritage, Geni or Ancestry opens in Strom as a family tree, on a computer and on a phone.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From GEDCOM → choose the file → Insert into tree
On a computer, the .ged file can also be dragged onto the window.
Strom does not open a zip: a file from Ancestry needs unpacking first.
Done when the screen shows a summary (number of people, relationships, photos) and, after confirming, the family tree.
A Strom backup file (.json) opens on any device.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From JSON → choose the file
On a computer, the file can also be dragged onto the window.
An encrypted file asks for its password when opened; a forgotten password cannot be recovered.
Done when the screen shows the family tree from the file.
The only reliable copy is a file. Each save downloads a new .json file to Downloads.
Ctrl + S (Mac ⌘ + S), or Actions (on a narrower screen ⋯) → Export… → Data backup (JSON)
Done when the screen shows “Saved to file” for a moment and the .json file in Downloads or in the chosen folder. “Only in browser” returns with the next change.
Next time, Strom opens the same way: same browser and same address, or the icon. On another device, only the file.
Strom is empty? The family tree is usually somewhere else →
Save to a file after every larger change.
Safari on a Mac deletes the data of a site not visited during 7 days of Safari use. Chrome or Edge are more reliable. In Safari, regular saving to a file matters even more.
Strom runs at stromapp.info/run/. Nothing gets installed and no account is needed.
https://stromapp.info/run/Done when the screen shows “Welcome to Strom” with the “Add first person” button and the “I have data elsewhere (GEDCOM from MyHeritage, Ancestry…)” link.
Safari can add Strom to the Dock. The Dock app, however, has its own data, separate from Safari.
File → Add to Dock → Add (macOS 14 and later), or the Share button → Add to Dock
Done when the screen shows the Strom icon in the Dock and Strom opened from it, empty.
The first person, then their parents and children. For example Anna Nováková, *1880.
Add first person
Done when the screen shows the card “Anna Nováková” in the tree.
A GEDCOM file from MyHeritage, Geni or Ancestry opens in Strom as a family tree, on a computer and on a phone.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From GEDCOM → choose the file → Insert into tree
On a computer, the .ged file can also be dragged onto the window.
Strom does not open a zip: a file from Ancestry needs unpacking first.
Done when the screen shows a summary (number of people, relationships, photos) and, after confirming, the family tree.
A Strom backup file (.json) opens on any device.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From JSON → choose the file
On a computer, the file can also be dragged onto the window.
An encrypted file asks for its password when opened; a forgotten password cannot be recovered.
Done when the screen shows the family tree from the file.
The only reliable copy is a file. Each save downloads a new .json file to Downloads.
Ctrl + S (Mac ⌘ + S), or Actions (on a narrower screen ⋯) → Export… → Data backup (JSON)
Done when the screen shows “Saved to file” for a moment and the .json file in Downloads or in the chosen folder. “Only in browser” returns with the next change.
Next time, Strom opens the same way: same browser and same address, or the icon. On another device, only the file.
Strom opens either always in Safari or always from the Dock. Each place has its own data.
Strom is empty? The family tree is usually somewhere else →
Save to a file after every larger change.
Open stromapp.info/run/ in Safari.
https://stromapp.info/run/Done when the screen shows Strom in Safari.
Add Strom to the home screen before entering any data. The family tree then belongs to the icon, not to Safari.
In Safari: ⋯ (or the Share button) → Share → scroll down → Add to Home Screen → leave Open as Web App on → Add
“Add to Home Screen” not in the list? At its end: Edit Actions → Add to Home Screen.
On iPad, the Share button (or ⋯) is at the top.
Done when the screen shows the Strom icon on the home screen.
From now on, Strom opens only via the home-screen icon, not in Safari.
Done when the screen shows Strom without the Safari address bar.
The first person, then their parents and children. For example Anna Nováková, *1880.
Add first person
Done when the screen shows the card “Anna Nováková” in the tree.
A GEDCOM file from MyHeritage, Geni or Ancestry opens in Strom as a family tree, on a computer and on a phone.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From GEDCOM → choose the file → Insert into tree
On iPhone, the downloaded file is in the Files app: iCloud Drive → Downloads.
Strom does not open a zip: a file from Ancestry needs unpacking first.
Done when the screen shows a summary (number of people, relationships, photos) and, after confirming, the family tree.
A Strom backup file (.json) opens on any device.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From JSON → choose the file
An encrypted file asks for its password when opened; a forgotten password cannot be recovered.
Done when the screen shows the family tree from the file.
On a phone via ⋯ (Actions) → Export… → Data backup (JSON). Each save is a new file. The file can also be sent to a computer.
⋯ (Actions) → Export… → Data backup (JSON)
iPhone and iPad: the file is in the Files app → Browse → iCloud Drive → Downloads.
Done when the screen shows the backup file in the Files app.
Next time only via the home-screen icon. The icon stays: a new icon starts empty.
Strom is empty? The family tree is usually somewhere else →
Save to a file after every larger change.
Strom runs at stromapp.info/run/. Nothing gets installed and no account is needed.
https://stromapp.info/run/Done when the screen shows “Welcome to Strom” with the “Add first person” button and the “I have data elsewhere (GEDCOM from MyHeritage, Ancestry…)” link.
Strom can be added to the home screen as an app. The data is the same as in Chrome.
Chrome: ⋮ → Install and create shortcut → Install
In an older Chrome the item is called “Add to Home screen”.
These steps are for Chrome. Other browsers (Samsung Internet, Firefox) differ.
The family tree is in Chrome. Before uninstalling or clearing Chrome’s data, a backup goes into a file.
Done when the screen shows the Strom icon on the phone's home screen.
The first person, then their parents and children. For example Anna Nováková, *1880.
Add first person
Done when the screen shows the card “Anna Nováková” in the tree.
A GEDCOM file from MyHeritage, Geni or Ancestry opens in Strom as a family tree, on a computer and on a phone.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From GEDCOM → choose the file → Insert into tree
On Android, the downloaded file is in the Files app, under Downloads.
Strom does not open a zip: a file from Ancestry needs unpacking first.
Done when the screen shows a summary (number of people, relationships, photos) and, after confirming, the family tree.
A Strom backup file (.json) opens on any device.
I have data elsewhere (GEDCOM from MyHeritage, Ancestry…) → From JSON → choose the file
An encrypted file asks for its password when opened; a forgotten password cannot be recovered.
Done when the screen shows the family tree from the file.
On a phone via ⋯ (Actions) → Export… → Data backup (JSON). Each save is a new file. The file can also be sent to a computer.
⋯ (Actions) → Export… → Data backup (JSON)
Android: the Files app, or in Chrome ⋮ → Downloads.
Done when the screen shows the backup file in Downloads.
Next time, Strom opens the same way: same browser and same address, or the icon. On another device, only the file.
Strom is empty? The family tree is usually somewhere else →
Save to a file after every larger change.
On a computer, ancestor research can be added to the family tree → Research guideResearch runs on a computer only.
All steps by combination:
Ancestor research works with an agent from another maker. The agent needs its own account.
The agent and its subscription: see Which AI agent.
Install and sign in to the agent before the next step. Without an agent on the computer, research from the app is set up as a Strom archive.
The AI subscription is separate; Strom Research charges nothing.
The agent's best model: research reads old handwriting, and a fast model makes mistakes.
When the subscription hits its limit, research stops and the findings stay saved.
Prices in USD before tax, from the makers’ pages, as of October 2026. The price in local currency and with tax shows when paying.
Done when the screen shows a signed-in agent: the app after sign-in, or the agent's command in the terminal without an error.
The Strom app prepares the line for this computer, together with this family tree.
In the app: Actions (on a narrower screen ⋯) → Ancestor research → Install on this computer → Copy
Done when the screen shows the line and the Copy button in the “Installing Strom Research” window.
The Run window, paste the line, Enter.
Win + R → paste the line (Ctrl + V) → Enter
Done when the screen shows a blue or black window with the lines “Downloading Node.js from nodejs.org…” and “Downloading Strom research…”.
The setup guide may offer its own git. Only Strom uses it, and nothing gets installed.
Done when the screen shows “Installed: <path>”.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
Questions 5–10 only with an agent. Which ones show depends on the computer.
Done when the screen shows “All set.” with the language and folder.
The agent opens with a prepared folder and a first message. Confirm the folder and send the message.
Confirm the folder → Send the message
Done when the screen shows the agent asking whom to look for. For example: “the Novák family, Anna Nováková *1880”.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
Ancestor research works with an agent from another maker. The agent needs its own account.
The agent and its subscription: see Which AI agent.
The setup guide installs Claude Code itself; a subscription is all that is needed.
The AI subscription is separate; Strom Research charges nothing.
The agent's best model: research reads old handwriting, and a fast model makes mistakes.
When the subscription hits its limit, research stops and the findings stay saved.
Prices in USD before tax, from the makers’ pages, as of October 2026. The price in local currency and with tax shows when paying.
Done when the screen shows a signed-in agent: the app after sign-in, or the agent's command in the terminal without an error.
The line for this computer. Research from the web starts with an empty family tree.
powershell -ExecutionPolicy Bypass -c "irm https://stromapp.info/research/install.ps1 | iex"Done when the screen shows “Copied”.
The Run window, paste the line, Enter.
Win + R → paste the line (Ctrl + V) → Enter
Done when the screen shows a blue or black window with the lines “Downloading Node.js from nodejs.org…” and “Downloading Strom research…”.
The setup guide may offer its own git. Only Strom uses it, and nothing gets installed.
Done when the screen shows “Installed: <path>”.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
With a Claude subscription: the first choice, installing Claude Code.
Questions 5–10 only with an agent. Which ones show depends on the computer.
Started from the web, research then asks for the family tree's name (“e.g. the family surname”) and starts empty.
Done when the screen shows “All set.” with the language and folder.
The agent opens with a prepared folder and a first message. Confirm the folder and send the message.
Confirm the folder → Send the message
On the first start of Claude Code installed by the setup guide, sign-in comes in a browser window.
Done when the screen shows the agent asking whom to look for. For example: “the Novák family, Anna Nováková *1880”.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
The Strom app prepares the line for this computer, together with this family tree.
In the app: Actions (on a narrower screen ⋯) → Ancestor research → Install on this computer → Copy
Done when the screen shows the line and the Copy button in the “Installing Strom Research” window.
The Run window, paste the line, Enter.
Win + R → paste the line (Ctrl + V) → Enter
Done when the screen shows a blue or black window with the lines “Downloading Node.js from nodejs.org…” and “Downloading Strom research…”.
The setup guide may offer its own git. Only Strom uses it, and nothing gets installed.
Done when the screen shows “Installed: <path>”.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
Questions 5–10 only with an agent. Which ones show depends on the computer.
Done when the screen shows “All set.” with the language and folder.
Research opens the Strom app in the browser and offers to hand over the family tree.
Keep saving the backup file (Ctrl+S).
Done when the screen shows “linked to research” at the tree in “Manage trees”, and “In sync with the research” at the tree's name.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
The line for this computer. Research from the web starts with an empty family tree.
powershell -ExecutionPolicy Bypass -c "irm https://stromapp.info/research/install.ps1 | iex"Done when the screen shows “Copied”.
The Run window, paste the line, Enter.
Win + R → paste the line (Ctrl + V) → Enter
Done when the screen shows a blue or black window with the lines “Downloading Node.js from nodejs.org…” and “Downloading Strom research…”.
The setup guide may offer its own git. Only Strom uses it, and nothing gets installed.
Done when the screen shows “Installed: <path>”.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
When no agent is found, the setup guide offers to install Claude Code, or just a Strom archive.
Questions 5–10 only with an agent. Which ones show depends on the computer.
Started from the web, research then asks for the family tree's name (“e.g. the family surname”) and starts empty.
Done when the screen shows “All set.” with the language and folder.
Research starts with an empty family tree. The tree from the app is handed over in the Strom app:
Actions → Ancestor research → Start research with this tree
The button shows once the setup guide allowed links from the app (the last question, Enter) and research has connected with the app at least once.
Images stay in the app.
Keep saving the backup file (Ctrl+S).
Done when the screen shows “linked to research” at the tree in “Manage trees”, and “In sync with the research” at the tree's name.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
Ancestor research works with an agent from another maker. The agent needs its own account.
The agent and its subscription: see Which AI agent.
Install and sign in to the agent before the next step. Without an agent on the computer, research from the app is set up as a Strom archive.
The AI subscription is separate; Strom Research charges nothing.
The agent's best model: research reads old handwriting, and a fast model makes mistakes.
When the subscription hits its limit, research stops and the findings stay saved.
Prices in USD before tax, from the makers’ pages, as of October 2026. The price in local currency and with tax shows when paying.
Done when the screen shows a signed-in agent: the app after sign-in, or the agent's command in the terminal without an error.
The Strom app prepares the line for this computer, together with this family tree.
In the app: Actions (on a narrower screen ⋯) → Ancestor research → Install on this computer → Copy
Done when the screen shows the line and the Copy button in the “Installing Strom Research” window.
Terminal, paste the line, Enter.
Open Terminal (⌘ + Space, type “Terminal”, Enter) → paste the line (⌘ + V) → Enter
Done when the screen shows “Downloading Node.js from nodejs.org…” in Terminal.
If git is missing, macOS opens the Command Line Tools window. Choosing “Install” and waiting is enough.
Usually a few minutes, on a slow connection up to 20 minutes.
Done when the screen shows the Apple window finished and Terminal carrying on.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
Questions 5–10 only with an agent. Which ones show depends on the computer.
Done when the screen shows “All set.” with the language and folder.
The agent's app opens with a prepared folder and a first message. Confirm the folder and send the message.
Confirm the folder → Send the message
Done when the screen shows the agent asking whom to look for. For example: “the Novák family, Anna Nováková *1880”.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
Ancestor research works with an agent from another maker. The agent needs its own account.
The agent and its subscription: see Which AI agent.
The setup guide installs Claude Code itself; a subscription is all that is needed.
The AI subscription is separate; Strom Research charges nothing.
The agent's best model: research reads old handwriting, and a fast model makes mistakes.
When the subscription hits its limit, research stops and the findings stay saved.
Prices in USD before tax, from the makers’ pages, as of October 2026. The price in local currency and with tax shows when paying.
Done when the screen shows a signed-in agent: the app after sign-in, or the agent's command in the terminal without an error.
The line for this computer. Research from the web starts with an empty family tree.
curl -fsSL https://stromapp.info/research/install.sh | shDone when the screen shows “Copied”.
Terminal, paste the line, Enter.
Open Terminal (⌘ + Space, type “Terminal”, Enter) → paste the line (⌘ + V) → Enter
Done when the screen shows “Downloading Node.js from nodejs.org…” in Terminal.
If git is missing, macOS opens the Command Line Tools window. Choosing “Install” and waiting is enough.
Usually a few minutes, on a slow connection up to 20 minutes.
Done when the screen shows the Apple window finished and Terminal carrying on.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
With a Claude subscription: the first choice, installing Claude Code.
Questions 5–10 only with an agent. Which ones show depends on the computer.
Started from the web, research then asks for the family tree's name (“e.g. the family surname”) and starts empty.
Done when the screen shows “All set.” with the language and folder.
The agent's app opens with a prepared folder and a first message. Confirm the folder and send the message.
Confirm the folder → Send the message
On the first start of Claude Code installed by the setup guide, sign-in comes in a browser window.
Done when the screen shows the agent asking whom to look for. For example: “the Novák family, Anna Nováková *1880”.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
The Strom app prepares the line for this computer, together with this family tree.
In the app: Actions (on a narrower screen ⋯) → Ancestor research → Install on this computer → Copy
Done when the screen shows the line and the Copy button in the “Installing Strom Research” window.
Terminal, paste the line, Enter.
Open Terminal (⌘ + Space, type “Terminal”, Enter) → paste the line (⌘ + V) → Enter
Done when the screen shows “Downloading Node.js from nodejs.org…” in Terminal.
If git is missing, macOS opens the Command Line Tools window. Choosing “Install” and waiting is enough.
Usually a few minutes, on a slow connection up to 20 minutes.
Done when the screen shows the Apple window finished and Terminal carrying on.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
Questions 5–10 only with an agent. Which ones show depends on the computer.
Done when the screen shows “All set.” with the language and folder.
Research opens the Strom app in the browser and offers to hand over the family tree.
Keep saving the backup file (Ctrl+S).
Done when the screen shows “linked to research” at the tree in “Manage trees”, and “In sync with the research” at the tree's name.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
The line for this computer. Research from the web starts with an empty family tree.
curl -fsSL https://stromapp.info/research/install.sh | shDone when the screen shows “Copied”.
Terminal, paste the line, Enter.
Open Terminal (⌘ + Space, type “Terminal”, Enter) → paste the line (⌘ + V) → Enter
Done when the screen shows “Downloading Node.js from nodejs.org…” in Terminal.
If git is missing, macOS opens the Command Line Tools window. Choosing “Install” and waiting is enough.
Usually a few minutes, on a slow connection up to 20 minutes.
Done when the screen shows the Apple window finished and Terminal carrying on.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
When no agent is found, the setup guide offers to install Claude Code, or just a Strom archive.
Questions 5–10 only with an agent. Which ones show depends on the computer.
Started from the web, research then asks for the family tree's name (“e.g. the family surname”) and starts empty.
Done when the screen shows “All set.” with the language and folder.
Research starts with an empty family tree. The tree from the app is handed over in the Strom app:
Actions → Ancestor research → Start research with this tree
The button shows once the setup guide allowed links from the app (the last question, Enter) and research has connected with the app at least once.
Images stay in the app.
Keep saving the backup file (Ctrl+S).
Done when the screen shows “linked to research” at the tree in “Manage trees”, and “In sync with the research” at the tree's name.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
Ancestor research works with an agent from another maker. The agent needs its own account.
The agent and its subscription: see Which AI agent.
Install and sign in to the agent before the next step. Without an agent on the computer, research from the app is set up as a Strom archive.
The AI subscription is separate; Strom Research charges nothing.
The agent's best model: research reads old handwriting, and a fast model makes mistakes.
When the subscription hits its limit, research stops and the findings stay saved.
Prices in USD before tax, from the makers’ pages, as of October 2026. The price in local currency and with tax shows when paying.
Done when the screen shows a signed-in agent: the app after sign-in, or the agent's command in the terminal without an error.
The Strom app prepares the line for this computer, together with this family tree.
In the app: Actions (on a narrower screen ⋯) → Ancestor research → Install on this computer → Copy
Done when the screen shows the line and the Copy button in the “Installing Strom Research” window.
Terminal, paste the line, Enter.
Open a terminal (often Ctrl + Alt + T) → paste the line (Ctrl + Shift + V, or right-click → Paste) → Enter
Done when the screen shows “Downloading Node.js from nodejs.org…”.
No window opens during installing. If git is missing, the setup guide prints a package manager command, e.g. sudo apt install git.
Done when the screen shows “Installed: <path>”.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
Questions 5–10 only with an agent. Which ones show depends on the computer.
Done when the screen shows “All set.” with the language and folder.
The agent's app opens with a prepared folder and a first message. Confirm the folder and send the message.
Confirm the folder → Send the message
Done when the screen shows the agent asking whom to look for. For example: “the Novák family, Anna Nováková *1880”.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
Ancestor research works with an agent from another maker. The agent needs its own account.
The agent and its subscription: see Which AI agent.
The setup guide installs Claude Code itself; a subscription is all that is needed.
The AI subscription is separate; Strom Research charges nothing.
The agent's best model: research reads old handwriting, and a fast model makes mistakes.
When the subscription hits its limit, research stops and the findings stay saved.
Prices in USD before tax, from the makers’ pages, as of October 2026. The price in local currency and with tax shows when paying.
Done when the screen shows a signed-in agent: the app after sign-in, or the agent's command in the terminal without an error.
The line for this computer. Research from the web starts with an empty family tree.
curl -fsSL https://stromapp.info/research/install.sh | shWithout curl:
wget -qO- https://stromapp.info/research/install.sh | shDone when the screen shows “Copied”.
Terminal, paste the line, Enter.
Open a terminal (often Ctrl + Alt + T) → paste the line (Ctrl + Shift + V, or right-click → Paste) → Enter
Done when the screen shows “Downloading Node.js from nodejs.org…”.
No window opens during installing. If git is missing, the setup guide prints a package manager command, e.g. sudo apt install git.
Done when the screen shows “Installed: <path>”.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
With a Claude subscription: the first choice, installing Claude Code.
Questions 5–10 only with an agent. Which ones show depends on the computer.
Started from the web, research then asks for the family tree's name (“e.g. the family surname”) and starts empty.
Done when the screen shows “All set.” with the language and folder.
The agent's app opens with a prepared folder and a first message. Confirm the folder and send the message.
Confirm the folder → Send the message
On the first start of Claude Code installed by the setup guide, sign-in comes in a browser window.
Done when the screen shows the agent asking whom to look for. For example: “the Novák family, Anna Nováková *1880”.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
The Strom app prepares the line for this computer, together with this family tree.
In the app: Actions (on a narrower screen ⋯) → Ancestor research → Install on this computer → Copy
Done when the screen shows the line and the Copy button in the “Installing Strom Research” window.
Terminal, paste the line, Enter.
Open a terminal (often Ctrl + Alt + T) → paste the line (Ctrl + Shift + V, or right-click → Paste) → Enter
Done when the screen shows “Downloading Node.js from nodejs.org…”.
No window opens during installing. If git is missing, the setup guide prints a package manager command, e.g. sudo apt install git.
Done when the screen shows “Installed: <path>”.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
Questions 5–10 only with an agent. Which ones show depends on the computer.
Done when the screen shows “All set.” with the language and folder.
Research opens the Strom app in the browser and offers to hand over the family tree.
Keep saving the backup file (Ctrl+S).
Done when the screen shows “linked to research” at the tree in “Manage trees”, and “In sync with the research” at the tree's name.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
The line for this computer. Research from the web starts with an empty family tree.
curl -fsSL https://stromapp.info/research/install.sh | shWithout curl:
wget -qO- https://stromapp.info/research/install.sh | shDone when the screen shows “Copied”.
Terminal, paste the line, Enter.
Open a terminal (often Ctrl + Alt + T) → paste the line (Ctrl + Shift + V, or right-click → Paste) → Enter
Done when the screen shows “Downloading Node.js from nodejs.org…”.
No window opens during installing. If git is missing, the setup guide prints a package manager command, e.g. sudo apt install git.
Done when the screen shows “Installed: <path>”.
A few questions. The suggested answer is prefilled, and Enter is enough.
Enter at every question
When no agent is found, the setup guide offers to install Claude Code, or just a Strom archive.
Questions 5–10 only with an agent. Which ones show depends on the computer.
Started from the web, research then asks for the family tree's name (“e.g. the family surname”) and starts empty.
Done when the screen shows “All set.” with the language and folder.
Research starts with an empty family tree. The tree from the app is handed over in the Strom app:
Actions → Ancestor research → Start research with this tree
The button shows once the setup guide allowed links from the app (the last question, Enter) and research has connected with the app at least once.
Images stay in the app.
Keep saving the backup file (Ctrl+S).
Done when the screen shows “linked to research” at the tree in “Manage trees”, and “In sync with the research” at the tree's name.
The Strom app talks to research directly, only on the same computer.
Chrome may ask “Access other apps and services on this device”: choose Allow.
With live following (“Follow live”), results arrive by themselves; the tree is locked meanwhile.
Otherwise a new version does not load by itself: a dot appears on ⋯, and the Research menu says “The research has a newer version” with a Load button. A backup is saved before loading.
Done when the screen shows a research result in the tree (live, or after Load).
A double-click on the “Strom výzkum” shortcut on the desktop, or the strom command in a new terminal window.
Strom výzkum.command on the DesktopStrom výzkum.lnkAn old terminal window does not know the new command.
From the app: Actions → Research (Continue with the agent, Open research, Follow live, Load new version). The menu is there only with links from the app on (question 13 of the setup guide, or strom link on); otherwise only “Start the research ↗”.
Done when the screen shows the research menu after the double-click.
Strom keeps everything right in the browser, with no account and no server, so the data stays on this device only. The browser usually keeps it for a long time, but does not guarantee it: it disappears when the browser is cleaned up, when site data is deleted, or when the app is uninstalled together with its data. That is why saving to a file regularly pays off (Ctrl+S, on a Mac ⌘S). The file can be opened again at any time, on another device too.
Ctrl+S or Actions → Export… → “Data backup (JSON)”. The file carries the family tree and photos and opens anywhere.
Every save downloads a new .json file. In Chrome and Edge the tree can be linked to one file (Actions → Export… → “Link to a file on disk…”) and saved into it again and again.
The file can be encrypted with a password if wished; without the password nobody opens it.
On a computer, ancestor research can be added, with an agent or without one.
Research guide → Without an agentStrom is found faster. The data stays where it was and does not replace a backup.
On iPhone, the icon has its own data.
When the browser deletes data, per device → Strom is empty? →
The family tree is usually not lost: it is somewhere other than where Strom just opened. The app cannot tell and shows an empty tree.
An empty Strom shows “Welcome to Strom” with the “Add first person” button and the “I have data elsewhere (GEDCOM from MyHeritage, Ancestry…)” link.
Chrome does not see what is in Safari, and a work profile does not see a personal one. The family tree is in the browser and profile where it was entered.
stromapp.info, www.stromapp.info and a downloaded strom.html are three places for the browser. strom.html shares data with all HTML files opened from disk in the same browser.
A family tree entered earlier via www.stromapp.info is stored separately in the browser.
Each place has its own data. Moving only by export and import.
Closing all private windows deletes everything. Strom warns about it only in Safari and Firefox, not in Chrome and Edge.
The family tree does not move to another device by itself, not even by sync. Only via a file.
It happens after clearing site data, with delete-on-close, in Safari after 7 days of use without a visit, after deleting the icon, or when space runs out.
The way back is the latest backup file: “I have data elsewhere (GEDCOM from MyHeritage, Ancestry…)” → “From JSON”, or on a computer the file dragged onto the window. Backups inside the app vanished with the data. A phone backup does not reliably restore it.
Next time: same browser, same address, or same icon. On iPhone only the home-screen icon; on a Mac either always Safari or always the Dock. Elsewhere only from the file.
Generations connected in one clean, interactive view, with panning and zooming through every branch.
The family tree
Map
People and sources
Overviews and checks
Print and share
Phone and tablet
The whole family tree saves to one file: a backup (JSON, photos included) or a standalone HTML file that opens in any browser. A file is also the only way to another device.
Everything runs in the browser on the device: no account, no server, no tracking. Only map tiles and place names for the map leave the device, and only with consent.
After the first visit, it works without internet too, in a tab and as an installed app. A new version announces itself in a bar; Refresh switches all windows.
Imports GEDCOM files from MyHeritage, Geni, Ancestry, Gramps and more, and exports in the standard that other genealogy programs read.
Photos, life events, document scans and proper source citations: everything a family chronicle needs, still in one portable file.
Free and open source (GNU AGPL v3 or later). The code is open to inspect and improve, so the app can be used with confidence.
Every fact carries its certainty: lead, possible, probable, proven. A child with only one known parent gets a “?” family.
A book cited on several pages gets a source for each page; the picker offers another page of the same book.
The Register card shows birth, baptism, marriage, death with its cause and burial, each with its place and full date. Five card types, plus a custom one.
With two or more marriages, each partner's card carries “1st ∞ 1866”, “2nd ∞ 1908”, and the partners stand in the order of the marriages.
Sample family trees come with the app (House of Tudor, Přemyslid dynasty), one click away.
No accounts, no server. One file travels by e-mail — and comes back smarter.
“Send to a relative” adds a personal note and puts the family tree into a single file for e-mail. Living people can be hidden automatically.
The relative just opens the file — a friendly welcome invites them to fill in their branch and send the file back with one click.
Strom recognises the returned file as part of the same family tree; the additions are reviewed side by side and merged in.
Works on the free Basic account too. Right after the import: “Download photos from the internet” in Strom, the links to the photos expire within a few days.
Profiles added by hand and the closest family can be exported. Free up to 5,000 profiles, with Geni Pro up to 50,000.
Only the owner of a tree can export it; no subscription is needed. Photos do not carry over: the export has none, and its links lead back to Ancestry only. Occupation data does not carry over to Strom.
A GEDCOM file cannot be downloaded from the shared FamilySearch tree (Family Tree). The former export via Innovate no longer works. Only a file uploaded to FamilySearch earlier can be downloaded (Genealogies, My Uploaded Files).
A GEDCOM file (.ged) from any program (Gramps, Family Tree Builder…) opens the same way.
Names, dates and places, parents and children, marriages, events and sources. Data without its own field goes into a note. Diacritics from ANSEL and ANSI files stay intact.
Import is a one-off copy. A newer file can be imported as a new tree, or merged: Actions → Tree → “Merge into another tree…”, also with “Only update existing people (don't add new)”.
Encryption: a JSON or HTML export can be encrypted with a password (“Encrypt with a password”, off by default); GEDCOM and CSV cannot. Without the password nobody opens the file, and a forgotten password cannot be recovered.
An optional add-on on a computer (Windows, Mac, Linux). With an AI agent it searches parish registers and archives, and the results show up in the app; without an agent it is free.
The app works on its own. The agent needs a subscription of its own with its maker; longer research tends to need a higher plan.
The family tree has two copies: in the app (the main one) and in the research. Changes pass between them only on request, or automatically.
Strom runs in Chrome, Edge, Firefox and Safari. Research connects with Chrome, Edge and Firefox.
Step by step for each device →
The browser holds the data: why a file is needed →
For advanced use: the whole app in one file. It has its own data, separate from stromapp.info. A downloaded file stays in the version it came in; it does not update itself · strom.html
Strom is free and open source (GNU AGPL v3 or later), and it always will be. A coffee supports its ongoing development.
