A quiet place to study chess
Chopening is a single-purpose tool: learn openings and understand your own games, without the noise of a full chess platform.
Yours alone
No account, no tracking, no cloud. Opening data ships with the app, Stockfish runs locally, and imported games never leave your device.
Instant
The engine runs locally in WebAssembly. No queues, no roundtrips, no rate limits — full Stockfish 18 strength in the tab.
Explained
Every opening line is annotated with the ideas behind the moves — why this square, why this order — so you learn the plan, not just a sequence.
? Do I need an account?
No. Chopening runs entirely in your browser. Your progress is stored on your own device using local storage — nothing is sent to a server.
? How does the engine work?
We run Stockfish 18 compiled to WebAssembly, directly in your browser tab. Analysis happens on your machine, which is why there's no server roundtrip and no rate limits.
? Where do the games come from?
Imports use the public Lichess and Chess.com APIs. You give a username, we fetch the recent public games — no password, no OAuth.
? Is it free?
Yes, completely. Chopening is an open study tool. If you'd like to support it, suggest an opening or report a bug.
Suggest an opening — or anything else.
Missing a line you love? Spotted a wrong move or a rough edge? Send it over. Every note is read.
Buy me a coffee