[Home](./index.md) > [@firebase/functions](./functions.md) > [getFunctions](./functions.getfunctions.md) ## getFunctions() function Returns a Functions instance for the given app. Signature: ```typescript export declare function getFunctions(app?: FirebaseApp, regionOrCustomDomain?: string): Functions; ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | app | [FirebaseApp](./app.firebaseapp.md) | The FirebaseApp to use. | | regionOrCustomDomain | string | one of: a) The region the callable functions are located in (ex: us-central1) b) A custom domain hosting the callable functions (ex: https://mydomain.com) | Returns: [Functions](./functions.functions.md)