React 19: Complete Guide to New Features

React 19 brings innovations that completely change how we write frontend applications.

Actions and Improved Forms

One of the biggest new features is Actions, which greatly simplifies form handling:

function Form() {
  async function submitForm(formData) {
    await saveToDatabase(formData);
  }

  return (
    <form action={submitForm}>
      <input name="email" />
      <button type="submit">Send</button>
    </form>
  );
}

Server Components

Server Components allow rendering components on the server, reducing JavaScript sent to the client.

New Compiler

The React compiler automatically optimizes your code, eliminating the need for useMemo and useCallback.

Conclusion

React 19 represents a huge leap in productivity and performance.