React DOM APIs

The react-dom package contains methods that are only supported for the web applications (which run in the browser DOM environment). They are not supported for React Native.


These APIs can be imported from your components. They are rarely used:

  • createPortal lets you render child components in a different part of the DOM tree.
  • flushSync lets you force React to flush a state update and update the DOM synchronously.

Resource Preloading APIs

These APIs can be used to make apps faster by pre-loading resources such as scripts, stylesheets, and fonts as soon as you know you need them, for example before navigating to another page where the resources will be used.

React-based frameworks frequently handle resource loading for you, so you might not have to call these APIs yourself. Consult your framework’s documentation for details.

  • prefetchDNS lets you prefetch the IP address of a DNS domain name that you expect to connect to.
  • preconnect lets you connect to a server you expect to request resources from, even if you don’t know what resources you’ll need yet.
  • preload lets you fetch a stylesheet, font, image, or external script that you expect to use.
  • preloadModule lets you fetch an ESM module that you expect to use.
  • preinit lets you fetch and evaluate an external script or fetch and insert a stylesheet.
  • preinitModule lets you fetch and evaluate an ESM module.

Entry points

The react-dom package provides two additional entry points:

  • react-dom/client contains APIs to render React components on the client (in the browser).
  • react-dom/server contains APIs to render React components on the server.

Removed APIs

These APIs were removed in React 19: