Mocha vs Jest

Free and open source

Free and open source

Free and open source. You pay in engineering time and CI minutes.

Free and open source. You pay in engineering time and CI minutes.

Everything, self-hosted

Everything, self-hosted

Widely used

OpenJS Foundation · since 2011

Category standard

OpenJS Foundation · since 2014

• Small, stable and predictable — it does one job and has done it the same way for years.
• Pick your own assertions, mocks and coverage rather than accepting a bundle.
• Excellent async and reporter support.

• Everything in one dependency, with defaults that work for most projects on day one.
• The largest ecosystem of matchers, reporters and framework presets in JavaScript.
• Snapshot testing is genuinely useful for serialisable output when used with restraint.

• No built-in mocking, snapshots, coverage or parallel-by-default execution.
• Assembling and documenting the stack is work every new project repeats.
• Fewer new projects adopt it; momentum sits with Vitest and Jest.

• Native ESM support remains awkward, and the Babel transform layer is a recurring configuration tax.
• Noticeably slower than Vitest on large suites.
• jsdom is not a browser; subtle DOM and CSS behaviour differs from reality.

Node.js services where you want explicit control over every part of the test stack.

Existing JavaScript codebases, React Native, and teams that value ecosystem depth over raw speed.