# fast-check

Property-based testing framework for JavaScript and TypeScript that generates inputs to check properties of code.


Source: https://findsoftware.frbit.cloud/fast-check/
Last reviewed: 2026-11-08
Listed since: 2026-11-08

## Record

### Links

- home: https://fast-check.dev/
- repository: https://github.com/dubzzz/fast-check
- docs: https://fast-check.dev/docs/tutorials/quick-start/
- plugins: https://fast-check.dev/docs/ecosystem/
- bluesky: https://bsky.app/profile/fast-check.dev

### Identity

- status: active
- maintainer: Nicolas DUBIEN
- maintainerType: individual
- parent: unknown
- firstRelease: 2017
- hqCountry: unknown

### Kind

- category: testing
- hosting: not applicable
- language: javascript
- runtime: node, deno, bun
- runtimeMin: node 12
- basedOn: unknown

### Content

- contentStore: not applicable
- databases: not applicable
- adminUi: not applicable
- headlessApi: not applicable
- templating: not applicable
- i18n: not applicable

### Rendering and deploy

- runsAs: unknown
- renderingModes: not applicable
- installMethod: npm

### License

- licenseModel: open-source
- license: MIT

### Releases

- currentMajor: 4
- latestReleaseDate: 2026-09-19

### Adoption

- githubStargazers: 5240
- packagistDownloads: not applicable
- npmWeeklyDownloads: 73156942
- contributors: 77
- pluginCount: unknown
- packagistMonthlyDownloads: unknown
- ecosystemsMonthlyDownloads: unknown
- httpArchiveSites: unknown
- wordpressActiveInstalls: unknown
- dependentRepos: unknown
- dependentPackages: unknown

### Sources

- urls: https://fast-check.dev/ (read 2026-11-08)
- urls: https://api.github.com/repos/dubzzz/fast-check (read 2026-11-08)
- urls: https://raw.githubusercontent.com/dubzzz/fast-check/main/packages/fast-check/README.md (read 2026-11-08)
- category: https://raw.githubusercontent.com/dubzzz/fast-check/main/packages/fast-check/README.md (read 2026-11-08)
- language: https://api.github.com/repos/dubzzz/fast-check (read 2026-11-08)
- runtime: https://github.com/dubzzz/fast-check/blob/v4.10.2/packages/fast-check/package.json (read 2026-11-08)
- runtime: https://fast-check.dev/docs/tutorials/setting-up-your-test-environment/property-based-testing-with-deno-test-runner/ (read 2026-11-08)
- runtime: https://fast-check.dev/docs/tutorials/setting-up-your-test-environment/property-based-testing-with-bun-test-runner/ (read 2026-11-08)
- runtimeMin: https://github.com/dubzzz/fast-check/blob/v4.10.2/packages/fast-check/package.json (read 2026-11-08)
- installMethod: https://raw.githubusercontent.com/dubzzz/fast-check/main/packages/fast-check/README.md (read 2026-11-08)
- urls: https://raw.githubusercontent.com/dubzzz/fast-check/main/packages/fast-check/README.md (read 2026-11-08)
- license: https://registry.npmjs.org/fast-check/latest (read 2026-11-08)
- maintainer: https://raw.githubusercontent.com/dubzzz/fast-check/main/LICENSE (read 2026-11-08)
- currentMajor: https://api.github.com/repos/dubzzz/fast-check/releases/latest (read 2026-11-08)
- latestReleaseDate: https://api.github.com/repos/dubzzz/fast-check/releases/latest (read 2026-11-08)
- firstRelease: https://api.github.com/repos/dubzzz/fast-check/releases (read 2026-11-08)
- githubStargazers: https://api.github.com/repos/dubzzz/fast-check (read 2026-11-08)
- contributors: https://api.github.com/repos/dubzzz/fast-check/contributors?per_page=1 (read 2026-11-08)
- npmWeeklyDownloads: https://api.npmjs.org/downloads/range/2026-11-01:2026-11-07/fast-check (read 2026-11-08)

## Notes

fast-check is a property-based testing library for JavaScript and TypeScript. A test states a property that should hold for every input that meets a precondition, and the library checks that property against many generated inputs.

A tutorial on the project's website covers the approach. The module is installed with npm, pnpm or yarn as a development dependency. The GitHub repository is a monorepo: beside the core package it holds integrations and a website.

---

Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Attributes are recorded, never scored; absent means unknown.
Credit, in full: FindSoftware, CC BY 4.0