React FAQ

The latest stable version of React is 19.2.4. There are currently 5 actively supported versions and 0 versions that have reached end of life. Visit the React Version Tracker on ReleaseRun for a complete breakdown of all versions, including release dates, support timelines, and end-of-life dates.

React 19 (released December 2024) introduced several improvements: React Server Components, Actions for form handling, the use() hook, document metadata support, and improved error handling. If your app uses a compatible framework (Next.js 15+, Remix) and your dependencies support React 19, upgrading is recommended. Run the React 19 codemods to automate most of the migration.

React 19 added Server Components as a first-class feature, Actions for streamlined form/mutation handling, the use() hook for reading promises and context, native document metadata management, and removed several deprecated APIs (including forwardRef, which is no longer needed). React 18 introduced concurrent rendering, automatic batching, Suspense improvements, and the useId hook.

React 17 is no longer actively maintained. While it continues to work, it does not receive new features or regular bug fixes. React 17 was a transitional release focused on enabling gradual upgrades. If you are still on React 17, plan to upgrade to at least React 18 for security patches and ecosystem compatibility.

Use the official React codemods (npx codemod) to automatically update deprecated patterns. Check that your component library (MUI, Chakra, Ant Design) supports the target version. Test thoroughly, especially around Suspense boundaries, effects, and any code relying on synchronous rendering. Upgrade React and ReactDOM together to the same version.

React Server Components (RSC) render on the server and send serialized output to the client. They can access backend resources (databases, file systems) directly without an API layer. They reduce client-side JavaScript bundle size because server component code never ships to the browser. RSC requires a compatible framework like Next.js to use.