Package

chess.js

[![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/jhlywa/chess.js/node.js.yml)](https://github.com/jhlywa/chess.js/actions) [![npm](https://img.shields.io/npm/v/chess.js?color=blue)](https://www.npmjs.com/package/chess.js) [

v1.4.0BSD-2-ClauseESM + CommonJSTypes: Bundled

$ npm install chess.js

npm GitHub Homepage

Key numbers

As of 25 Sept 2026

Weekly downloads: 122.3k; +168% over 12 months
Gzip bundle size: -; No Bundlephobia data
Dependencies: 0; Direct, from package.json
Last release: -; v1.4.0
GitHub stars: 4.4k; 988 forks
Open issues / PRs: 26 / 20
Contributors: -
Commits, last 52 weeks: 3

Downloads

Last week 2026-09-15 to 2026-09-21

Weekly npm downloads, one point per week, weeks starting 23 Sept 2025 to 15 Sept 2026. The y axis starts at zero.

122,334 downloads last week, 617,345 in the last month. The 12-month change of +168% compares the average of the last 4 weeks with the first 4 weeks of the series.

Maintenance

Releases, last 12 months: -
Latest version: 1.4.0
First published: -
Last push to GitHub: 11 Aug 202644 days before the snapshot
Repository archived: No
Open issues: 26
Open pull requests: 20
Commits, last 52 weeks: 3
Dependents on npm: -

Major versions

Recent releases

Compatibility

Module format: ESM + CommonJSFrom package.json type, main and exports fields
TypeScript types: Bundled
Node.js engine range: Not declared
Runtimes: -
Unpacked size (npm): 707 kB
Dependencies (0): None

Install

npm install chess.js

CDN

jsDelivr: 186.9k requests in 30 days

jsDelivrhttps://cdn.jsdelivr.net/npm/chess.js@1.4.0/
unpkghttps://unpkg.com/chess.js@1.4.0/
esm.shhttps://esm.sh/chess.js@1.4.0

Sources: npm registry, npm downloads API, GitHub API, jsDelivr. Data fetched 25 Sept 2026.

Indexability: Not indexed (discovery only): no category.