[Home](./index.md) > [@firebase/auth](./auth.md) > [PhoneAuthCredential](./auth.phoneauthcredential.md) > [fromJSON](./auth.phoneauthcredential.fromjson.md) ## PhoneAuthCredential.fromJSON() method Generates a phone credential based on a plain object or a JSON string. Signature: ```typescript static fromJSON(json: object | string): PhoneAuthCredential | null; ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | json | object \| string | | Returns: [PhoneAuthCredential](./auth.phoneauthcredential.md) \| null