chaijs/chai
BDD / TDD assertion framework for node.js and the browser that can be paired with any testing framework. observed · 2026-08-28
Health v2 · maintenance only
86/100
- Activity 99
- Release rhythm 62
- Longevity 100
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-03. Adoption (stars, forks) is never an input.
- gap_med: 3
- age_days: 5383
- days_rel: 254
- days_push: 9
- n_releases_24m: 14
Adoption not part of the score
8269 stars · 723 forks observed · 2026-08-28
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded
Chai is a BDD/TDD assertion library for Node.js and the browser that can be paired with any JavaScript testing framework. It offers three assertion styles (assert, expect, should) and an extensible plugin API.
Use cases
- write assertions for javascript unit tests
- use expect/should style BDD assertions with mocha
- assert deep equality and object properties in tests
- add custom assertions via a plugin
- test code in the browser and node with the same assertion library
When to choose
- you need expressive, chainable assertions independent of your test runner
- you want a mature, widely adopted assertion library with a plugin ecosystem
- you need both TDD assert-style and BDD expect/should styles
When to avoid
- your test framework already bundles its own assertion API you prefer (e.g. vitest/jest expect)
- you need a full test runner, not just assertions
Facets
library · maturity stable
testing testing developer-tools web-development browser cross-platform assertions bdd tdd javascript test-framework-agnostic plugin-system nodejs
8 sources
- readme: https://github.com/chaijs/chai · fetched 2026-08-28 · aa9ab4436212
- homepage: https://chaijs.github.io · fetched 2026-08-29 · d025df0adea2
- site_page: https://www.chaijs.com/guide/installation · fetched 2026-08-29 · e4b06268ee45
- site_page: https://www.chaijs.com/guide · fetched 2026-08-29 · 8c315918bad8
- registry_npm: https://registry.npmjs.org/chai · fetched 2026-08-29 · bf5c835ce21e
- site_page: https://www.chaijs.com/releases · fetched 2026-08-29 · 6b8b90d7a6d4
- site_page: https://www.chaijs.com/api · fetched 2026-08-29 · e51ba32bd046
- site_page: https://www.chaijs.com/plugins/chai-webdriver · fetched 2026-08-29 · c32203a140c0
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| chaijs/chai | main | 86 |
For agents
Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem