ChessGrader / Review Lichess games
Game review for Lichess players: grades, not just blunders.
Lichess already gives you free unlimited engine analysis — genuinely. ChessGrader adds the layer it deliberately leaves out: a full grade for every move, an estimated game rating, and drills for your mistakes.
First, the honest part
Lichess's server analysis is free, unlimited, and strong — Stockfish searching millions of nodes per move on their hardware, no daily cap, no paid tier. If all you want is an eval graph and your blunders flagged, Lichess already does that well and we're not going to pretend otherwise. (We compared the big two properly in Lichess vs Chess.com analysis.)
So why point ChessGrader at your Lichess games at all? Because Lichess stops at three labels.
What ChessGrader adds on top
- The full grade ladder. Lichess marks Inaccuracy, Mistake, and Blunder — only what went wrong. ChessGrader grades every move: Brilliant, Great, Best, Excellent, Good, Book, Inaccuracy, Miss, Mistake, Blunder. You find out what you did right, and every threshold is published.
- Brilliant and Great detection. Sound sacrifices and only-moves get flagged — and only after a 600,000-node verification search with the engine's two best lines, so the label means something. Here's what actually triggers a Brilliant.
- Estimated game rating. A rough strength read from your centipawn loss in that game. Lichess doesn't offer one. Treat it as a vibe, not a measurement.
- Mistake drills. Replay each error until you'd find the right move at the board, instead of nodding at the graph and queuing the next blitz game.
- Plain-language explanations of what each mistake gave away, not just a centipawn number.
ChessGrader vs Lichess analysis
| ChessGrader | Lichess server analysis | |
|---|---|---|
| Price / limits | Free, unlimited | Free, unlimited |
| Move labels | Full ladder: Brilliant to Blunder (10 grades) | Inaccuracy, Mistake, Blunder only |
| Positive-move recognition | Yes — Brilliant, Great, Best, Excellent | No |
| Accuracy + ACPL | Yes (same documented Lichess formula) | Yes |
| Estimated game rating | Yes | No |
| Mistake drills | Yes | No (separate puzzle features) |
| Engine search | 100k nodes/move, key moments verified at 600k | ~2M+ nodes/move on their servers |
| Where it runs | Your browser — games never uploaded | Lichess servers |
Note the engine row: Lichess's server search is deeper than ChessGrader's first pass. That's a real difference and we won't spin it. ChessGrader's fixed 100,000-node budget exists so every device produces identical grades, and the moments that decide labels get re-searched at 600,000 nodes. For grading purposes the two agree on the overwhelming majority of moves — the full reasoning is on the methodology page.
How it works
Type your Lichess username. ChessGrader fetches your games from the Lichess public API — no login, no password, no account connection — and analyzes them with Stockfish 17.1 running as WebAssembly in your browser. Nothing is uploaded; there is no server to upload to. Accuracy uses Lichess's own documented formula, so that number should feel familiar. You can also paste any PGN directly.
Same win-probability curve family as Lichess, same accuracy formula, published grade thresholds. ChessGrader is not trying to out-engine Lichess — it's finishing the report Lichess starts.
Frequently asked questions
Isn't Lichess analysis already free and unlimited?
Yes, and it is good. Lichess gives every user unlimited server-side Stockfish analysis with an eval graph, accuracy, and centipawn loss. ChessGrader adds what Lichess leaves out: a grade for every move including Brilliant, Great, Best and Miss, an estimated game rating, mistake drills, and plain-language explanations.
What grades does ChessGrader give that Lichess does not?
Lichess labels only Inaccuracy, Mistake, and Blunder. ChessGrader grades every move on a ten-step ladder: Brilliant, Great, Best, Excellent, Good, Book, Inaccuracy, Miss, Mistake, and Blunder, with published win-probability thresholds for each.
Is it safe to type my Lichess username?
Yes. ChessGrader reads your games through the Lichess public API — the same games anyone can already see on your profile. There is no login, no password, and no account connection, and the analysis itself runs entirely in your browser.
Will ChessGrader's accuracy match the number Lichess shows?
Very closely, because ChessGrader uses Lichess's own documented accuracy formula. Small differences can appear because the engines search different node counts, but the method — per-move exponential decay combined with a volatility-weighted and harmonic mean — is the same.
Is ChessGrader's engine weaker than Lichess server analysis?
Lichess's servers search more nodes per move than ChessGrader's 100,000-node first pass, so on raw depth, yes. ChessGrader compensates where it matters: potential blunders, brilliancies, and big swings are re-searched at 600,000 nodes with the top two lines before any major label is awarded. For move grading the two agree on the vast majority of moves.
What is the estimated game rating and should I trust it?
It is a rough strength estimate fitted from your average centipawn loss against community rating data, rounded to the nearest 25. Treat it as a vibe, not a measurement — a single game is a small sample and time control changes everything.
Can I review Lichess games from other players or from years ago?
Yes. Any standard-chess game available through the Lichess public API can be reviewed, however old, and you can look up any public username. Variants like Chess960, Atomic, and Crazyhouse are not supported.