Stockfish — the chess engine this site sends to your browser

Beside this file sits a compiled copy of the Stockfish chess engine, which this
site sends to your browser to analyse chess positions:

    stockfish-18-lite-single.js
    stockfish-18-lite-single.wasm

They are free software under the GNU General Public License, version 3. The
full text of that licence is beside them, in Copying.txt.

THE EXACT VERSION
    Stockfish.js 18.0.8, the lite single-threaded build,
    taken unmodified from the 'stockfish' package on npm.

THE SOURCE FOR THAT VERSION
    https://github.com/nmrugg/stockfish.js/tree/v18.0.8
    That tag carries the engine source under src/ and the build script build.js.

THE UPSTREAM ENGINE IT IS BUILT FROM
    https://github.com/official-stockfish/Stockfish/tree/sf_18
    Stockfish.js's own README at v18.0.8 says: "Stockfish.js is
    currently updated to Stockfish 18."

COPYRIGHT, reproduced from the loader's own header comment
    Stockfish.js 18 (c) 2026, Chess.com, LLC
    Based on Stockfish (c) T. Romstad, M. Costalba, J. Kiiski, G. Linscott and
    other contributors.
    Nets by Linmiao Xu (linrock)

The same credits as a page on this site: /credits