What makes it free
Because Stockfish runs locally on your device, there are no server costs—so no reason to charge you.
Truly unlimited
No daily analysis cap. No game limit. Analyze every game in your history if you want—Stockfish runs on your device, so there are no server costs to meter.
No account required
Just enter your Chess.com or Lichess username and go. No sign-up, no email, no password. Your session is local to your browser.
Stockfish 17.1 engine
The same world-class engine used by GMs. Running via WebAssembly in your browser at depths from 13 (fast) to 50 (deep precision).
Works offline
After the first load, Chessomy works without internet. Analyze saved games on a plane, in a park, anywhere.
Chessomy vs typical analysis tools
Common questions
Is Chessomy really free?
Yes. All features—game analysis, blunder puzzles, statistics, the Nemesis bot—are free. No premium tier, no credit card, no paywall.
Why is it free?
Chessomy runs Stockfish on your device, not our servers. There are no compute costs for analysis, so there's no reason to charge for it.
Does free mean limited?
No. You can analyze as many games as you like at any depth. The only limit is your computer's processing speed, which affects how fast each position evaluates.
How do I start?
Enter your Chess.com or Lichess username on the Review Games page, or paste a PGN directly. Stockfish starts analyzing immediately.