Privacy Policy

Last updated 13 July 2026

Simple Sequence Diagram is built to need as little of your data as possible: there are no accounts, no names, and no email addresses. This page explains the data the service does handle, why, and how you can access or remove it.

What we collect

An anonymous ownership cookie.

When you first create or edit a diagram, your browser is given a random, unguessable identifier in an HTTP-only cookie (seqdiag_owner), kept for up to a year. It contains no personal information — it's how the service recognizes "this browser's diagrams" the next time you visit, without asking you to sign up. Only a one-way hash of this token is stored on the server.

The diagrams you create — plus the IP address and country of whoever last saved them.

Titles, diagram source text, and any logo image you add are stored so you can come back to them later. Each diagram also records the IP address and country of the browser that created or most recently edited it, visible to the site operator in the admin panel. This is separate from the ownership cookie above, which stays the same across visits even if your IP address changes.

Pageview analytics — page, referrer, IP address, country, and coarse device/browser.

Each time the app loads, we record the page path, the referring URL (if any), your IP address, a country derived from it, a coarse device/browser category (e.g. "Mobile, Safari" — derived from your browser's User-Agent header, which is never itself stored), and a timestamp — so we can see how many people use the site and roughly where from. This does not use cookies and is not linked to the ownership cookie above.

Why we process this

Each item above exists only to provide the specific feature you're using — saving and retrieving your own diagrams, and understanding who's using the site and from where. We don't use this data for advertising, profiling, or anything beyond operating the service, and we don't share it with third parties. There are no third-party analytics providers, ad networks, or trackers on this site.

How long we keep it

Diagrams — and the IP/country stored alongside them — are kept until you delete the diagram.
The ownership cookie expires after one year of inactivity.
Pageview analytics records, including IP addresses, are retained to track usage trends over time.

Your rights

Because diagrams aren't tied to a name or email, most of your rights under GDPR are already built directly into the app rather than requiring a request to us:

Access / export — use the TXT or Backup buttons to download your diagrams at any time.
Deletion — delete any diagram directly from the sidebar, which also removes the IP/country stored with it; clearing your browser's cookies disconnects you from any diagrams tied to that identifier.
Objection / questions — email contact@simplesequencediagram.se, including for requests about pageview analytics records, which aren't self-service.

You also have the right to lodge a complaint with your local data protection authority — in Sweden, the Integritetsskyddsmyndigheten (IMY).

Changes

If this policy changes, the "last updated" date at the top of this page will change accordingly.