About RatingLeaks

RatingLeaks turns your own Lichess and Chess.com games into a short, honest report: where your rating points go, what you already do well, and one habit to work on first. It started as a deep review a coach did of one player's 1,246 games, which found that most of the usual advice didn't apply to him and that a few specific habits were costing him real points. RatingLeaks does that review automatically, for anyone.

Who makes it

RatingLeaks is made by Chess.sg Pte. Ltd., a chess school in Singapore that teaches group classes, one-to-one lessons and camps, and runs weekly tournaments.

How the analysis works

Your browser reads your public rated games from Lichess and Chess.com. Nothing is fetched on our servers.
Stockfish 19 runs on your own device and checks each position of your recent games.
Every finding compares you with the opponents in the same games, checked the same way. They're about your rating, so it's a fair baseline.
Win chances use the same formula as Lichess. About 7 rating points are worth 1% of score at an even rating.
A leak only counts as confirmed when the difference is unlikely to be chance, and its price is shrunk when the evidence is thinner or the sample is small.
Any computer explanation of chess can be wrong in the details. Check concrete lines on a board.

Open-source software

Stockfish 19, the chess engine, by the Stockfish developers, licensed under the GNU General Public License v3. We serve the unmodified "lite, single-threaded" WebAssembly build from Stockfish.js by Nathan Rugg (npm package stockfish, version 19.0.1), with the network by Chris Bao. Source code: official-stockfish/Stockfish and nmrugg/stockfish.js at v19.0.1. Licence text: COPYING.
chess.js by Jeff Hlywa, BSD 2-Clause licence.
Chess pieces ("cburnett") by Colin M.L. Burnett, available under the GPL, BSD and GFDL licences.

Data sources

Game data comes from the Lichess API and the Chess.com Published-Data API. RatingLeaks is independent and is not affiliated with or endorsed by either site.