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Package

is-what

JS type check (TypeScript supported) functions like `isPlainObject() isArray()` etc. A simple & small integration.

v5.5.0, 22 Sept 2025MITESM onlyTypes: NoneTypeScript tooling
$ npm install is-what
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Key numbers

As of 25 Sept 2026
Weekly downloads
14.3m
+61% over 12 months
Gzip bundle size
-
No Bundlephobia data
Dependencies
0
Direct, from package.json
Last release
1 year ago
v5.5.0
GitHub stars
201
19 forks
Open issues / PRs
11 / 3
Contributors
-
Commits, last 52 weeks
10

Downloads

Last week 2026-09-15 to 2026-09-21
010m20m30mSept 2025Mar 2026Sept 2026High 21.1m (18 Aug 2026)Low 5.9m (23 Dec 2025)
Weekly npm downloads, one point per week, weeks starting 23 Sept 2025 to 15 Sept 2026. The y axis starts at zero.

14,328,816 downloads last week, 72,212,634 in the last month. The 12-month change of +61% compares the average of the last 4 weeks with the first 4 weeks of the series.

Maintenance

Releases, last 12 months
071 in total
Latest version
5.5.0, 22 Sept 20251 year ago
First published
19 Jun 2018
Last push to GitHub
23 Sept 20261 day before the snapshot
Repository archived
No
Open issues
11
Open pull requests
3
Commits, last 52 weeks
10
Dependents on npm
121

Major versions

  1. v5 first release 5.0.0, 24 May 2024
  2. v4 first release 4.0.0, 8 Mar 2021
  3. v3 first release 3.0.0, 5 Oct 2018
  4. v2 first release 2.0.0, 10 Sept 2018
  5. v1 first release 1.0.0, 19 Jun 2018

Recent releases

VersionPublished
5.5.022 Sept 2025
5.4.01 Sept 2025
5.3.01 Sept 2025
5.2.124 Mar 2025
5.2.014 Feb 2025
5.1.114 Feb 2025
5.1.014 Feb 2025
5.0.27 Jun 2024
5.0.15 Jun 2024
5.0.024 May 2024
4.1.1626 Oct 2023
4.1.156 Jun 2023
4.1.133 Jun 2023
4.1.1231 May 2023

Compatibility

Module format
ESM onlyFrom package.json type, main and exports fields
TypeScript types
None
Node.js engine range
>=18
Runtimes
-
Unpacked size (npm)
37 kB
Dependencies (0)
None

Install

npm install is-what

CDN

  • jsDelivrhttps://cdn.jsdelivr.net/npm/is-what@5.5.0/
  • unpkghttps://unpkg.com/is-what@5.5.0/
  • esm.shhttps://esm.sh/is-what@5.5.0

Alternatives

PackageWeekly downloadsGzipLast releaseModuleComparison
typescript209.2m-2 months agoESM only-
Sources: npm registry, npm downloads API, GitHub API. Data fetched 25 Sept 2026.

Indexability: Indexed.