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Your chess progress — XP, streak, mastery, saved games — is stored in your own browser and is never sent to us. There are no accounts, and we hold no database of your games. The only third party involved is our advertising provider, described below.
OMSR Chess is a static website. The chess engine, the lessons and your progress all run inside your
browser. Progress is written to localStorage on your device under the key
omsr-chess-v1. It contains your XP, day streak, hearts, per-item mastery levels and your
display settings.
We cannot read that data. It never travels to a server we control. Clearing your browser storage deletes it permanently, and you can export or wipe it yourself from the Profile screen.
This site is free and is supported in part by advertising. When advertising is enabled, we use Google AdSense. Google and its partners may use cookies or similar technologies to serve ads based on your prior visits to this and other websites.
Rewarded ads — the optional short ad you can watch to refill hearts — follow the same rules. Watching one is always your choice; hearts also refill for free over time, so waiting costs nothing but time. Using an ad blocker is fine and will not restrict any part of the site.
There is no paid subscription and nothing on this site is behind a paywall. If you choose to donate, the payment is handled entirely by the donation platform you pick (for example UPI, Ko-fi, Buy Me a Coffee, PayPal or GitHub Sponsors), each under its own privacy policy. We never see or store your payment details, and donating is not linked to your use of the site in any way.
If analytics are enabled on this deployment, we use a privacy-friendly, cookieless provider that records aggregate page views only — no cross-site tracking, no personal profiles, no fingerprinting. If a cookie-based analytics provider is ever enabled instead, this policy will be updated first.
The site is a set of static files served from a content delivery network. There is no application server and no database, so nothing you do here is recorded on our side — your games, progress and settings live only in your own browser's storage. The CDN keeps standard edge access logs (IP address, user agent, requested URL, timestamp) for security and troubleshooting, under its own privacy policy. These are retained for a short period and are not used to build a profile of you.
This site is suitable for all ages, but it is not directed at children under 13, and we do not knowingly collect personal information from them. If advertising is shown to a user we believe may be a child, it is served as non-personalised.
Because we hold almost nothing about you, most data requests resolve instantly: clear your browser storage and every trace of your use of this site is gone.
If you are in the EU, UK, India or a similar jurisdiction, you have the right to access, correct, delete and port your data, and to object to processing. Exercise any of these by emailing us.
If this policy changes materially, we will update the date at the top and note the change on the site.
Questions about privacy: [email protected]
This document is provided as a practical starting point, not legal advice. If you operate this site commercially, have a lawyer review it against the rules that apply where you and your users live.