Privacy policy
Game analysis runs on your own machine. This page sets out the few places where data does reach a server, and what happens to it there.
Updated
Last updated 8 September 2026. This policy covers rvchess.com and the ReviewChess browser extension.
Analysis stays on your device
Stockfish is compiled to WebAssembly and runs in your browser. The games you review, the positions the engine examines and the results it produces are held on your own machine and are not uploaded. You do not need an account to review a game, and reviewing one anonymously leaves nothing on any server.
What is stored, and only when you ask for it
- Accounts. If you create one, we store your email address, and the display name and avatar your sign-in provider gives us. Passwords are stored only as a slow one-way hash; passkeys are stored as public keys. We never hold a password in a form we can read. Sessions and sign-in links are stored hashed and expire.
- Saved analyses. Reviews you choose to save to your account are stored against your account so you can open them from another device. They are visible to you, not to other users.
- Contributed games. Only if you explicitly turn on game contribution. The stored copy keeps the moves and the result, rating and time-control headers, and drops the player names.
- Feedback. Whatever you type into the feedback box, plus an email address if you choose to give one so we can reply.
- Puzzles and shared links. Guess-the-Elo answers and any position or game you deliberately create a share link for.
Analytics
We use Vercel Analytics and Vercel Speed Insights to count page views and measure load performance. They are cookieless and do not build a cross-site profile of you. Server logs and rate limiting see your IP address, as any web server does; IP addresses are not linked to your account or your games.
The browser extension
The ReviewChess extension for Chrome and Firefox adds a review button to Chess.com game pages. It stores nothing, sends no requests of its own, and contains no analytics or tracking code. When you click the button it opens the matching rvchess.com address in a new tab, tagged so we can see how many visits come from the extension. From that point the rest of this policy applies.
What we never do
We do not sell your data, we do not share it with advertisers or data brokers, and we do not use it to build advertising profiles. We use it only to run the features described above.
Keeping and deleting data
Delete your account and we delete your account record, your saved analyses and your sign-in credentials with it. Contributed games are de-identified when they are stored and cannot be traced back to you afterwards, so they stay. To ask for a copy of your data or to have it deleted, write to support@rvchess.com.
Children
RV Chess is not directed at children under 13 and we do not knowingly collect their data. If you believe a child has given us data, write to the address above and we will remove it.
Changes
If this policy changes materially, the date at the top of this page changes with it.