---
modificationDate: March 06, 2026
title: Send notifications with FCM legacy server
description: Learn how to send notifications with FCM legacy server.
---
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# Send notifications with FCM legacy server
Learn how to send notifications with FCM legacy server.
> For the complete documentation index, see [llms.txt](/llms.txt). Use this file to discover all available pages.
> This page is archived. See [Push Notifications guide](/push-notifications/overview) for up-to-date information.
> For documentation on communicating with the newer FCMv1 service, see [Send notifications with FCMv1 and APNs](/push-notifications/sending-notifications-custom). This guide is based on [Google's documentation](https://firebase.google.com/docs/cloud-messaging/http-server-ref), and this section covers the basics to get you started.
Communicating with FCM is done by sending a POST request. However, before sending or receiving any notifications, you'll need to follow the steps to [configure FCM](/push-notifications/push-notifications-setup#android) to configure FCM and get your `FCM-SERVER-KEY`.
```js
await fetch('https://fcm.googleapis.com/fcm/send', {
method: 'POST',
headers: {
'Content-Type': 'application/json',
Authorization: `key=`,
},
body: JSON.stringify({
to: '',
priority: 'normal',
data: {
experienceId: '@yourExpoUsername/yourProjectSlug',
scopeKey: '@yourExpoUsername/yourProjectSlug',
title: "\uD83D\uDCE7 You've got mail",
message: 'Hello world! \uD83C\uDF10',
},
}),
});
```
**The `experienceId` and `scopeKey` fields are required**. Otherwise, your notifications will not go through to your app. FCM has a list of supported fields in the [notification payload](https://firebase.google.com/docs/cloud-messaging/http-server-ref#notification-payload-support), and you can see which ones are supported by `expo-notifications` on Android by looking at the [FirebaseRemoteMessage](/versions/latest/sdk/notifications#firebaseremotemessage).
FCM also provides some [server-side libraries in a few different languages](https://firebase.google.com/docs/cloud-messaging/send/admin-sdk) you can use instead of raw `fetch` requests.
### How to find FCM server key
Your FCM server key can be found by making sure you've followed the [configuration steps](/push-notifications/push-notifications-setup#android), and instead of uploading your FCM key to Expo, you would use that key directly in your server (as the `FCM-SERVER-KEY` in the previous example).
## Payload format
```json
{
"token": native device token string,
"collapse_key": string that identifies notification as collapsible,
"priority": "normal" || "high",
"data": {
"experienceId": "@yourExpoUsername/yourProjectSlug",
"scopeKey": "@yourExpoUsername/yourProjectSlug",
"title": title of your message,
"message": body of your message,
"channelId": the android channel ID associated with this notification,
"categoryId": the category associated with this notification,
"icon": the icon to show with this notification,
"link": the link this notification should open,
"sound": boolean or the custom sound file you'd like to play,
"vibrate": "true" | "false" | number[],
"priority": AndroidNotificationPriority, // https://docs.expo.dev/versions/latest/sdk/notifications/#androidnotificationpriority
"badge": the number to set the icon badge to,
"body": { object of key-value pairs }
}
}
```
### Firebase notification types
There are two types of Firebase Cloud Messaging messages: [notification and data messages](https://firebase.google.com/docs/cloud-messaging/customize-messages/set-message-type#notification-messages-with-optional-data-payload).
1. **Notification** messages are only handled (and displayed) by the Firebase library. They don't necessarily wake the app, and `expo-notifications` will not be made aware that your app has received any notification.
2. **Data** messages are not handled by the Firebase library. They are immediately handed off to your app for processing. That's where `expo-notifications` interprets the data payload and takes action based on that data. **In almost all cases, this is the type of notification you have to send.**
If you send a message of type **notification** instead of **data** directly through Firebase, you won't know if a user interacted with the notification (no `onNotificationResponse` event available), and you won't be able to parse the notification payload for any data in your notification event-related listeners.
> Using notification-type messages can be beneficial when you need a configuration option that is not yet exposed by `expo-notifications`. Generally, it may lead to less predictable situations than using data-type messages. However, you may need to report any issue you encounter directly to Google.
Below is an example of each type using Node.js Firebase Admin SDK to send data-type messages instead of notification-type:
```js
const devicePushToken = /* ... */;
const options = /* ... */;
// ❌ The following payload has a root-level notification object and
// it will not trigger expo-notifications and may not work as expected.
admin.messaging().sendToDevice(
devicePushToken,
{
notification: {
title: "This is a notification-type message",
body: "`expo-notifications` will never see this 😢",
},
data: {
photoId: 42,
},
},
options
);
// ✅ There is no "notification" key in the root level of the payload
// so the message is a "data" message, thus triggering expo-notifications.
admin.messaging().sendToDevice(
devicePushToken,
{
data: {
title: "This is a data-type message",
message: "`expo-notifications` events will be triggered 🤗",
// ⚠️ Notice the schema of this payload is different
// than that of Firebase SDK. What is there called "body"
// here is a "message". For more info see:
// https://docs.expo.dev/versions/latest/sdk/notifications/#android-push-notification-payload-specification
body: // As per Android payload format specified above, the
JSON.stringify({ photoId: 42 }), // additional "data" should be placed under "body" key.
},
},
options
);
```