---
tags:
  - chess
  - stockfish
  - wasm
license: gpl-3.0
---

# Stockfish.js WASM (GPL-3.0)

Stockfish 18 compiled to JavaScript/WebAssembly for browser use.
Hosted here for CORS-friendly access from web chess applications.

**License: GPL-3.0** — Stockfish is free software under the GNU General Public License.

## Files

| File | Size | Description |
|------|------|-------------|
| stockfish-18-lite-single.js | ~21KB | JS loader (single-threaded, lite NNUE) |
| stockfish.wasm | ~7.3MB | WASM binary (lite NNUE network embedded) |

## Source

Built from [nmrugg/stockfish.js](https://github.com/nmrugg/stockfish.js) v18.0.0.
Original Stockfish engine: [official-stockfish/Stockfish](https://github.com/official-stockfish/Stockfish).

## Usage

Load as a Web Worker. The JS loader fetches `stockfish.wasm` from the same directory.
Communicates via UCI protocol over `postMessage`.

Used by [CrispChess](https://github.com/CrispStrobe/CrispChess) — downloaded at runtime,
never bundled with the MIT-licensed app.