Last updated: November 2026.
The short version: TheirInheritance works entirely in your browser. Your estate file and its figures are never sent anywhere — the app never attaches them to anything it sends, and there is no account. The one thing that does leave your device is feedback you choose to type and send (see Feedback below), and it carries whatever you type, so a figure you type into it is sent too.
Three things are remembered between visits, and none of them holds any figure from your file: which file you opened, so you do not have to find it again; whether you chose light or dark mode; and any feedback you have sent from this device, so you can find or remove it. That feedback list keeps the words exactly as you typed them, so it holds a figure only if you typed one. You can clear the file at any time. The app also keeps a copy of its own files, its pages, scripts and fonts, in your browser so it can open without a connection; that copy holds no data of yours.
Your estate file. The estate_data.json you load is read locally by
your browser and its contents are held only in your device's memory. It is never
uploaded. When you save, the file is written back to your own disk (or downloaded as a
copy). The app does not send it to us or to any third party. A strict Content-Security-Policy stops the
page sending data to any other website, and the only server endpoint the app has is the
feedback form, which is given the words you type and nothing from your file.
Cloud-synced folders. If you choose to keep your file in a Google Drive, iCloud, Dropbox or OneDrive synced folder, that file is synced to your own cloud account by your own software — that is your choice and outside this app. The app itself sends your file nowhere.
The site is served by our host (Cloudflare Pages). Like any website, the host may process standard request information — such as your IP address — in server logs to deliver and protect the page. This is handled by the host under its own data-processing terms. If you send feedback, the request is handled by a Cloudflare function that sees your IP address while it does so; the code uses it only to limit how often one address can send, keeps it in memory, and does not pass it on or save it. We set no cookies. Cloudflare counts visits to these pages and presses of the button that opens the app, with no cookies and never any estate figures.
Apart from feedback you choose to send, we hold no personal data about you, so there is nothing else for us to access, correct, export or delete. Your data lives solely with you. Under UK GDPR this design is "data protection by design and by default".
You can install TheirInheritance and run it with no internet connection at all — the clearest proof that your estate data never leaves your device. It is read and written on your own machine, and nothing about it is sent anywhere.
Feedback is the one thing that leaves your device. If you choose to send feedback, the words you type are sent to us and kept until we delete them. They go to a Cloudflare function and are stored as an issue on GitHub, a third-party service that holds them for us. You see exactly what is sent, and nothing is sent unless you agree to it. Your estate data is never part of it. The app never attaches any figure from your file. The words are sent exactly as you type them, so please leave out names, figures and anything personal.
To ask for feedback you sent to be deleted, write to [email protected].
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