[Home](./index.md) > [@firebase/auth](./auth.md) > [AuthCredential](./auth.authcredential.md) ## AuthCredential class Interface that represents the credentials returned by an [AuthProvider](./auth.authprovider.md). Signature: ```typescript export declare class AuthCredential ``` ## Remarks Implementations specify the details about each auth provider's credential requirements. The constructor for this class is marked as internal. Third-party code should not call the constructor directly or create subclasses that extend the `AuthCredential` class. ## Properties | Property | Modifiers | Type | Description | | --- | --- | --- | --- | | [providerId](./auth.authcredential.providerid.md) | | string | The authentication provider ID for the credential. | | [signInMethod](./auth.authcredential.signinmethod.md) | | string | The authentication sign in method for the credential. | ## Methods | Method | Modifiers | Description | | --- | --- | --- | | [toJSON()](./auth.authcredential.tojson.md) | | Returns a JSON-serializable representation of this object. |