Package

is-fn

Check if a value is a function

v3.0.0, 3 May 2021MITESM onlyTypes: None

$ npm install is-fn

npm GitHub Homepage

Key numbers

As of 25 Sept 2026

Weekly downloads: 126.8k; -19% over 12 months
Gzip bundle size: -; No Bundlephobia data
Dependencies: 0; Direct, from package.json
Last release: 5 years ago; v3.0.0
GitHub stars: 29; 7 forks
Open issues / PRs: 0 / 0
Contributors: -
Commits, last 52 weeks: 0

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.

126,760 downloads last week, 558,544 in the last month. The 12-month change of -19% compares the average of the last 4 weeks with the first 4 weeks of the series.

Maintenance

Releases, last 12 months: -
Latest version: 3.0.0, 3 May 20215 years ago
First published: -
Last push to GitHub: 3 May 20211,970 days before the snapshot
Repository archived: No
Open issues: 0
Open pull requests: 0
Commits, last 52 weeks: 0
Dependents on npm: 43

Major versions

Recent releases

Compatibility

Module format: ESM onlyFrom package.json type, main and exports fields
TypeScript types: None
Node.js engine range: >=12
Runtimes: -
Unpacked size (npm): 2.4 kB
Dependencies (0): None

Install

npm install is-fn

CDN

jsDelivrhttps://cdn.jsdelivr.net/npm/is-fn@3.0.0/
unpkghttps://unpkg.com/is-fn@3.0.0/
esm.shhttps://esm.sh/is-fn@3.0.0

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

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