[Home](./index.md) > [@firebase/storage](./storage.md) > [useStorageEmulator](./storage.usestorageemulator.md) ## useStorageEmulator() function Modify this `StorageService` instance to communicate with the Cloud Storage emulator. Signature: ```typescript export declare function useStorageEmulator(storage: StorageService, host: string, port: number): void; ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | storage | [StorageService](./storage.storageservice.md) | The StorageService instance | | host | string | The emulator host (ex: localhost) | | port | number | The emulator port (ex: 5001) | Returns: void