Don’t just find the blunder. Understand it.
Free, unlimited game review with board-proven explanations. Powered by Stockfish 18 in your browser—no Premium or account.
On Chess.com? Keep the game link and add rv.
chess.com/game/12345678rvchess.com/game/12345678
On Chrome? Add the free one-click review button.
Chess analysis in your browser
Review Chess.com, Lichess or PGN games and find the moves that changed the result. See the accuracy calculation, mistakes and move classifications instead of only a raw engine number.
Accurate, never invented
There is no language model in the review. Every label comes from Stockfish 18's evaluation and published thresholds, and an explanation such as a fork or a hanging piece is shown only when replaying the moves on the board proves it. When nothing can be proven, the review says only what the engine found — it never fills the gap with a guess.
What a review tells you
Every move is scored against Stockfish 18's own choice, then labelled: best, excellent, good, inaccuracy, mistake, blunder, or brilliant. You get an accuracy figure and a performance rating for each side, an evaluation bar, and a graph you can click, or arrow-key through, to reach the moment the game swung. The thresholds behind each label are published.
Bring a game in three ways
Paste a PGN from any site, paste a Chess.com or Lichess game link, or search a Chess.com username to pick from recent games. Typing rv in front of chess.com in a game URL opens the review directly.
Follow the better line
At every mistake, see the stronger move and Stockfish's continuation. Click any move in the line to preview the resulting position on the board, then return to the game and keep stepping through it.
Or open the analysis board
The sandbox is a free chess analysis board: set up any position by hand or paste a FEN, play both sides, and get live Stockfish evaluation with best-move arrows as you move.
Everything else it does
Saved reviews you can reopen instantly, shareable position cards, adjustable engine depth, keyboard and phone-friendly boards. See the full feature list, or start with what a game review gives you.
Questions
Is RV Chess free?
Yes. Game review is free, with no account and no limit on how many games you analyse.
How do I review a Chess.com game?
Type rv in front of chess.com in a saved live, daily, or computer game link, paste the link into the import box, or look the game up by Chess.com username.
How do I review a Lichess game?
Paste the game link into the import box. Any Lichess address works: the plain lichess.org/abcd1234 form, the longer one your own games get, and the /white and /black variants.
Are the explanations AI-generated?
No. There is no language model in the review. Move labels come from Stockfish 18's evaluations and published thresholds, and an explanation such as a fork or a hanging piece is shown only when replaying the moves on the board proves it. When nothing can be proven, the review says only what the engine found.
Which engine does the analysis?
Stockfish 18, compiled to WebAssembly. Analysis stays inside your browser. Completed games are contributed only if you explicitly enable the de-identified research option.
Can I analyse a single position instead of a whole game?
Yes. Open the sandbox, set the position up by dragging pieces or pasting a FEN, and Stockfish evaluates it live as you play both sides, with the best moves drawn on the board.
Can I review a PGN without an account?
Yes. Paste the PGN into the import panel and the review starts on its own. Nothing is uploaded and no sign-in is required.
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