Firebase Cloud Messaging

Firebase Cloud Messaging (FCM) is a cross-platform messaging solution that lets you reliably send messages.

Using FCM, you can notify a client app that new email or other data is available to sync. You can send notification messages to drive user re-engagement and retention. For use cases such as instant messaging, a message can transfer a payload of up to 4096 bytes to a client app.


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iOS+ Android Web Flutter

Unity C++

Key capabilities

Send notification messages or data messages Send notification messages that are displayed to your user. Or send data messages and determine completely what happens in your application code. See Message types.
Versatile message targeting Distribute messages to your client app in any of 3 ways—to single devices, to groups of devices, or to devices subscribed to topics.

How does it work?

An FCM implementation includes two main components for sending and receiving:

  1. A trusted environment such as Cloud Functions for Firebase or an app server on which to build, target, and send messages.
  2. An Apple, Android, or web (JavaScript) client app that receives messages via the corresponding platform-specific transport service.

You can send messages via the Firebase Admin SDK or the FCM server protocol. You can use the Notifications composer for testing and to send marketing or engagement messages using powerful built-in targeting and analytics or custom imported segments.

See the architectural overview for more detail and important information about the components of FCM.

Implementation path

Set up the FCM SDK Set up Firebase and FCM on your app according to the setup instructions for your platform.
Develop your client app Add message handling, topic subscription logic, or other optional features to your client app. During the development, you can easily send test messages from the Notifications composer.
Develop your app server Decide whether you want to use the Firebase Admin SDK or the server protocol to create your sending logic—logic to authenticate, build send requests, handle responses, and so on. Then build out the logic in your trusted environment.

Next steps