[Home](./index.md) > [@firebase/auth](./auth.md) > [ReactNativeAsyncStorage](./auth.reactnativeasyncstorage.md) > [setItem](./auth.reactnativeasyncstorage.setitem.md) ## ReactNativeAsyncStorage.setItem() method Persist an item in storage. Signature: ```typescript setItem(key: string, value: string): Promise; ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | key | string | storage key. | | value | string | storage value. | Returns: Promise<void>