ChessGrader / Terms of Use
Terms of Use
ChessGrader is a free chess analysis tool that runs entirely in your browser. These terms are the agreement between you and us when you use it. They are written to be read, not skimmed past.
1. Who we are
ChessGrader (“ChessGrader”, “we”, “us”) is an independent website operated by a private developer based in Australia. We are not a company, a chess federation, or a partner of any chess platform. The service is provided free of charge, with no accounts, no subscriptions, and no payments of any kind.
You can reach us at contact@chessgrader.com. That address is the correct route for legal notices, privacy requests, intellectual-property complaints, and takedown requests, and we treat mail sent there seriously.
2. Accepting these terms
By using ChessGrader you agree to these terms. If you do not agree, please do not use the site. If you are under 18, use ChessGrader only with the involvement of a parent or guardian. We may update these terms from time to time; the effective date above changes when we do, and continuing to use the site after that means you accept the update.
3. What ChessGrader is — and is not
ChessGrader takes a chess game you supply and produces a review: a grade for each move, an accuracy score, an evaluation graph, an estimated performance rating, and written commentary. The analysis is performed by a chess engine (Stockfish) compiled to WebAssembly and executed inside your own browser, on your own device. We do not run analysis on a server, and your games are not sent to us.
ChessGrader is not a chess-playing service, a rating authority, a coaching credential, or a substitute for a human coach. Everything it outputs is a computed estimate produced by software, described in full on our methodology page.
4. Independence and trademarks
ChessGrader is not affiliated with, endorsed by, sponsored by, or connected to Chess.com, Lichess.org, the Stockfish developers, FIDE, or any other chess organisation.
“Chess.com”, “Lichess”, “Stockfish” and other names, logos, and marks referred to on this site belong to their respective owners. We use them only descriptively — to say truthfully which platforms ChessGrader can import games from — which is nominative fair use. We do not copy those platforms’ board designs, piece sets, sounds, or move-classification artwork, and our move grades are computed by our own published method rather than reproduced from theirs. Full attribution is on our licenses page. If you own one of these marks and believe we have overstepped, email us and we will fix it promptly.
5. Importing games
ChessGrader can fetch games two ways: by requesting them from a chess platform’s public interface using a username you type in, or from a PGN you paste or upload. Those requests are made by your browser, directly to that platform.
You agree that:
- you will only enter usernames and import games you are entitled to look at — in practice, your own games or games already published publicly by the platform;
- your use of Chess.com and Lichess data remains subject to their terms of service and API conditions, and nothing here overrides those;
- you will not use ChessGrader to make bulk, automated, or high-volume requests to any third-party platform, to build a competing dataset, or to circumvent any platform’s rate limits or access controls.
Public chess games often contain other players’ usernames. Treat that data with the same care you would want applied to your own, and do not use ChessGrader to compile information about a specific person for harassment, doxxing, or profiling.
6. No use during live play
This one matters. ChessGrader is a tool for reviewing games that have already finished. Using an engine — ours or anyone else’s — to assist a game in progress is cheating, breaks the rules of every major chess platform, and can get your account permanently banned. You must not use ChessGrader, or any output from it, to obtain assistance in a live or correspondence game where outside help is not permitted. If you do, that is entirely on you.
7. Acceptable use
You agree not to:
- scrape, crawl, or systematically download ChessGrader, or run automated agents against it beyond ordinary personal use;
- attempt to interfere with, overload, or gain unauthorised access to the site or anything connected to it;
- remove, obscure, or alter any copyright, licence, or attribution notice on the site or in the files it serves;
- use the site in a way that breaks any law that applies to you.
8. Accuracy of the analysis
Engine evaluations are estimates, and so is everything ChessGrader builds on top of them. Move grades, accuracy percentages, estimated ratings, opening identification, and written commentary can all be wrong, and are calculated at a fixed search budget that a deeper analysis may contradict. Our labels and thresholds are our own; they will not always match the labels another site puts on the same move, and neither result is authoritative.
Do not rely on ChessGrader output as evidence in a cheating investigation, a tournament dispute, a rating appeal, or any other proceeding where a person’s standing is at stake. It is not designed or validated for that, and we make no representation that it is fit for it.
9. Availability
ChessGrader is provided free and as-is. We may change, suspend, limit, or discontinue any part of it — or the whole thing — at any time, without notice and without liability. Because the site depends on third-party platforms for game imports, features can also break for reasons outside our control. Anything stored in your browser is yours to keep; see the privacy policy for what that is and how to clear it.
10. Intellectual property
The ChessGrader name, site design, written content, and original source code are ours, and are protected by copyright. The site also incorporates open-source software under licences that grant you rights independent of these terms — including copyleft licences. Where an open-source licence applies to a component, that licence governs that component, and nothing in this section limits the rights it gives you. See the licenses page for the component list and how to obtain source.
Games, PGNs, and text you supply remain yours. We do not receive, store, or claim any rights in them; they never leave your browser.
11. Disclaimers and liability
To the maximum extent permitted by law, ChessGrader is provided “as is” and “as available”, without warranties of any kind, express or implied, including implied warranties of merchantability, fitness for a particular purpose, accuracy, and non-infringement. We do not warrant that the site will be uninterrupted, error-free, or that its analysis will be correct.
To the maximum extent permitted by law, we are not liable for any indirect, incidental, special, consequential, or punitive loss, or for any loss of data, rating points, prize money, opportunity, or goodwill, arising out of your use of ChessGrader. Where liability cannot lawfully be excluded, our total aggregate liability to you is limited to AUD $100.
Australian Consumer Law
Nothing in these terms excludes, restricts, or modifies any guarantee, right, or remedy you have under the Australian Consumer Law (Schedule 2 to the Competition and Consumer Act 2010 (Cth)) or any other law that cannot lawfully be excluded. If a consumer guarantee applies to the supply of ChessGrader to you and we fail to comply with it, and that failure does not amount to a major failure, our liability is limited — at our option — to supplying the service again, or to paying the cost of having it supplied again.
12. Indemnity
You agree to indemnify us against claims, losses, and reasonable costs arising from your breach of these terms, your misuse of the site, or your infringement of anyone else’s rights — including any use of ChessGrader to assist play in a live game.
13. Governing law
These terms are governed by the laws of New South Wales, Australia. You and we submit to the non-exclusive jurisdiction of the courts of New South Wales and the courts entitled to hear appeals from them. If you are a consumer resident elsewhere, this does not deprive you of the protection of mandatory consumer laws in your own country.
14. General
If any provision of these terms is found unenforceable, it is severed and the rest continues to apply. Our failure to enforce a provision is not a waiver of it. These terms, together with the privacy policy and licenses page, are the entire agreement between us about ChessGrader.
15. Contact
Questions, complaints, or notices: contact@chessgrader.com.