[Home](./index.md) > [@firebase/messaging](./messaging.md) > [getMessaging](./messaging.getmessaging.md) ## getMessaging() function Retrieves a Firebase Cloud Messaging instance. Signature: ```typescript export declare function getMessagingInWindow(app?: FirebaseApp): FirebaseMessaging; ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | app | [FirebaseApp](./app.firebaseapp.md) | | Returns: [FirebaseMessaging](./messaging.firebasemessaging.md) The Firebase Cloud Messaging instance associated with the provided firebase app.