Build components in isolation, then test the stories you already wrote.
Storybook renders UI components in isolation as 'stories'. Beyond documentation, the test runner executes interaction tests inside each story, and the same stories feed visual regression tools like Chromatic and accessibility checks via the a11y addon. Writing a story therefore produces documentation, a visual baseline and a test fixture at once.
Best for
Free and open source
Open sourceFree tier: Everything, self-hosted
What drives the bill: Storybook itself is free. Chromatic, the hosted visual-review service from the same team, is a separate paid product.
Check current pricing on Chromatic / OSS community’s siteFigures are indicative and were last reviewed August 2026. Vendors change pricing often; confirm before you commit.
No reviews of Storybook yet. If you have used it in anger, yours would be the first.
If Storybook is not the right fit, these solve the same problem differently.
Unit & Component
Query the DOM the way a user would, not the way the framework does.
Visual Testing
Visual testing and review built by the Storybook team, for Storybook.
E2E & UI Testing
Developer-first browser testing with an interactive runner developers actually enjoy.