ChessGrader / Review Chess.com games
Ran out of free Game Reviews? Review every chess.com game here.
Chess.com's free plan gives you one Game Review per day. ChessGrader reviews every game in your chess.com archive — same style of report, unlimited, no signup. Type your username and it just works.
The one-per-day limit, plainly
On chess.com's free plan you get one Game Review per day. Play three games, pick one to learn from. The plain analysis board stays available, but blunder and mistake details there — and the full coach commentary — sit behind a paid membership. We wrote up exactly what the limit covers if you want the details.
That's not a scandal. Game Review runs on chess.com's servers, and servers cost money. ChessGrader dodges the cost a different way: the analysis runs on your device, so serving one more review costs us nothing — which is why there's no cap.
How ChessGrader works with your chess.com games
Chess.com publishes every account's finished games through a public API. ChessGrader fetches your archive from that API by username — the same data anyone can see on your profile.
- No login, no password, no OAuth. You type a username, not credentials. ChessGrader never connects to your account and couldn't change anything on it if it wanted to.
- No upload. Games go from chess.com's API straight into your browser, where Stockfish 17.1 (compiled to WebAssembly) analyzes them locally. We never see your games.
- No account with us either. No signup, no email, no daily limit.
What the report includes
- Every move graded on the full ladder — Brilliant, Great, Best, Excellent, Good, Book, Inaccuracy, Miss, Mistake, Blunder — with published thresholds for each label.
- Accuracy score, computed with the documented Lichess formula, so you can compare it against rating benchmarks.
- Estimated game rating from your centipawn loss. A vibe, not a measurement.
- Eval graph showing exactly where the game turned.
- Mistake drills — replay your errors until the right move is the one your hand plays.
- Plain-language explanations of what each mistake actually gave away.
What's different from chess.com's Game Review
| ChessGrader | Chess.com Game Review (free) | |
|---|---|---|
| Reviews per day | Unlimited | 1 |
| Signup required | No | Yes (chess.com account) |
| Where analysis runs | Your browser (Stockfish 17.1 WebAssembly) | Chess.com's servers |
| Blunder/mistake details | Every game, free | Requires a paid plan in analysis |
| Move-label formulas | Fully published at /methodology | Proprietary |
| Coach commentary | Plain-language explanations | Full coach needs a paid membership |
| Also reviews Lichess games and pasted PGNs | Yes | No |
The honest caveats
ChessGrader's numbers won't be pixel-identical to chess.com's. Their exact accuracy formula and Brilliant detection are proprietary; ours are built from engine output and published math. In practice, grades differ by at most a step and accuracy by a couple of points — same engine family, same ideas, different secret sauce (except ours isn't secret).
Every formula ChessGrader uses — win probability, the 100,000-node budget, the 600,000-node verification pass, every grade threshold — is documented on the methodology page. If you think a grade is wrong, you can check the math yourself.
Also worth knowing: analysis speed depends on your device (a modern phone takes about a minute per game), and ChessGrader only handles standard chess — no variants, no Chess960.
Frequently asked questions
Is it safe to type my chess.com username into ChessGrader?
Yes. ChessGrader only reads the public game archive that chess.com already exposes for every account through its public API. Your username is not a secret — anyone can see your finished games on your profile. ChessGrader never asks for or receives anything private.
Does ChessGrader need my chess.com password?
No, never. There is no login, no password field, and no account connection of any kind. ChessGrader fetches your public games by username and analyzes them in your browser. If a chess analysis site ever asks for your chess.com password, close the tab.
Why is ChessGrader free when chess.com charges for unlimited reviews?
Because the analysis runs on your device, not ours. Chess.com runs its engine on servers, which cost money per review, so a daily cap makes sense for them. ChessGrader runs Stockfish 17.1 as WebAssembly in your browser, so an extra review costs us nothing.
Will ChessGrader's grades match chess.com's exactly?
Usually within one grade step, and accuracy usually within a couple of points, but not identically. Chess.com's exact formulas and Brilliant detection are proprietary, while ChessGrader's are fully published on its methodology page. Both use Stockfish; the labeling math differs slightly.
Can I review old chess.com games, not just recent ones?
Yes. Chess.com publishes your full archive of finished games through its public API, organized by month, and ChessGrader can fetch and review any of them. There is no limit on how far back you go or how many you review.
Does it work for rated and unrated games? Blitz and bullet too?
Yes. Any standard chess game in your chess.com archive can be reviewed — rated or unrated, bullet through daily. Variants like Chess960, bughouse, and crazyhouse are not supported.
Where does my game data go?
From the chess.com public API directly into your browser, and no further. The Stockfish analysis runs entirely on your device, and reports are cached in your browser storage. Nothing is uploaded to a ChessGrader server.