Privacy

The SansTypo browser extension. Last updated 22 September 2026.

Short version: the extension sends nothing to us or to anyone else. It makes no network requests at all. There is no server, no account and no analytics.

What the extension reads

When it is checking a page, the extension reads the text in the field you are typing in, and the origin of the page you are on (for example https://example.com). It does not read the rest of the page, and it does not read the path or the query string of the address, so it does not know which page of a site you are on.

It never reads password fields, one-time code fields, or any field a site marks as card-number or password entry. It skips read-only and disabled fields. It skips private and incognito windows unless you have explicitly turned that behaviour off in the SansTypo desktop application.

Where that text goes

With no SansTypo desktop application installed, the text goes nowhere. The checking runs inside the extension, on your own computer, using a small set of wording rules built into it.

With the SansTypo desktop application running, the text and the page’s origin are sent to that application over a connection to 127.0.0.1 — your own computer, addressing itself. That connection cannot leave your machine. The application and the extension prove a shared code to each other before any text is sent, so another program on your computer cannot receive it. The application checks the text and sends back the corrections.

Nothing is transmitted to us, and there is no “us” to transmit it to: the extension contains no address of any server.

What the extension stores

Three values, in your browser’s local extension storage, on your device: whether the extension is switched on, the pairing code for the desktop application, and a flag recording that a one-time explanation has been shown. None of it is synchronised to any account. No text you type is stored.

What the extension does not do

• It does not collect, sell, rent or share any personal information.
• It does not use your data for anything other than checking the text you asked it to check.
• It does not use your data to determine creditworthiness or for lending.
• It does not show advertising and contains no advertising or tracking code.
• It does not require an account and cannot be signed in to.

Site access

Installing the extension grants it access to no website. Until you choose “Allow All Sites” in its popup, it can read only the single page you right-clicked in or opened the popup on, and only while you are on it. You can withdraw all-sites access at any time from your browser’s extensions page, and the extension stops reading pages immediately when you do.

Children

The extension is not directed at children and collects nothing from anyone.

Changes

If this ever changes, this page changes with it, and the change is disclosed in the extension before it takes effect.

Contact

Open an issue with anything about privacy, and it will be answered there in public.