Testem vs Vitest
Testem
github.com
Vitest
vitest.devSide by side
| Figure | Testem | Vitest |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | — | Yes |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| Plans published | 1 | 1 |
| Spec score · JavaScript Testing Frameworks | 7.7 (#10) | 7.6 (#12) |
| Browser testing | It can launch real browsers, including Chrome, Firefox, Safari, and Edge, and provides a Headless Chrome launcher. | Browser Mode runs tests natively in a browser and supports Playwright and WebdriverIO providers. |
| Security | The repository page shows no security advisories. | The maker's announcement says it plans an enterprise JavaScript tooling solution designed for scale and security requirements; it does not state a Vitest security certification. |
Plans
In their own words
Testem
Testem is a JavaScript test runner for running tests in Node.js, real desktop browsers, or a launcher you configure. It supports Jasmine, QUnit, Mocha, and custom framework adapters, and can be used for unit, integration, end-to-end-style, or custom test setups. Browser runs can use Chrome, Firefox, Safari, or Edge, including a Headless Chrome launcher. In development mode, a terminal interface watches project files and reruns tests after relevant changes; CI mode can run tests in available browsers in parallel. Testem includes CI reporters for TAP, dot, xunit, and TeamCity, with custom reporters available. Listed preprocessing support includes Babel, TypeScript, Browserify, ESLint, JSHint, JSLint, and CoffeeScript. Its API provides startDev, startCI, and startServer modes, and coverage reporting is supported. It works with GitHub Actions, Jenkins, and TeamCity. Testem is free and open source under the MIT license, and runs on Linux, macOS, and Windows. It requires a supported Node.js runtime: ^22.17.0, ^24.0.0, or >=26.0.0.
Vitest
Vitest is a free and open-source testing framework powered by Vite, though it can also run without Vite. It can reuse Vite configuration, plugins, resolvers, and transform pipelines. Jest-compatible APIs cover assertions, snapshots, and mocking, which can support migration from Jest. Watch mode reruns tests related to changed source or test files, and TypeScript, JSX, and ES modules work out of the box. Browser Mode runs tests in a browser and supports Playwright and WebdriverIO providers. Component testing covers Vue, React, Svelte, Lit, Marko, and other frameworks. Vitest supports coverage through V8 or Istanbul, benchmarking powered by Tinybench, parallel execution, parameterized cases, and property-based checks. An official Visual Studio Code extension is available, and the framework can be tried in StackBlitz without local installation. The listed requirements are Vite 6.4.0 or later and Node 22.12.0 or later. Help is available through the Vitest Discord community and GitHub Discussions.