[Home](./index.md) > [@firebase/auth](./auth.md) > [UserCredential](./auth.usercredential.md) ## UserCredential interface A structure containing a [User](./auth.user.md), an [AuthCredential](./auth.authcredential.md), the [OperationType](./auth.operationtype.md), and any additional user information that was returned from the identity provider. Signature: ```typescript export interface UserCredential ``` ## Remarks `operationType` could be [OperationType.SIGN\_IN](./auth.operationtype.sign_in.md) for a sign-in operation, [OperationType.LINK](./auth.operationtype.link.md) for a linking operation and [OperationType.REAUTHENTICATE](./auth.operationtype.reauthenticate.md) for a reauthentication operation. ## Properties | Property | Type | Description | | --- | --- | --- | | [operationType](./auth.usercredential.operationtype.md) | [OperationType](./auth.operationtype.md) | The type of operation which was used to authenticate the user (such as sign-in or link). | | [providerId](./auth.usercredential.providerid.md) | string \| null | The provider which was used to authenticate the user. | | [user](./auth.usercredential.user.md) | [User](./auth.user.md) | The user authenticated by this credential. |