# Authenticate
source: https://developer.mastercard.com/mastercard-checkout-solutions/documentation/sdk-reference/authenticate/index.md

This method invokes the user flow to authenticate a consumer identity.

The following table depicts the usage of this method for our products:

|                                                                             Product                                                                             |                                                                                  Usage                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [Secure Card on File](https://developer.mastercard.com/mastercard-checkout-solutions/documentation/sdk-reference/authenticate/authenticate_cardonfile/index.md) | This method is used for invoking the authentication UI to perform identification and verification (ID\&V) for a given authentication method.                             |
| [Click to Pay](https://developer.mastercard.com/mastercard-checkout-solutions/documentation/sdk-reference/authenticate/authenticate_clicktopay/index.md)        | This method launches the Mastercard-hosted UI to handle consumer authentication---unifying the user flow for passkey for login, OTP, and optional 'Remember me' consent. |

> #### Applicable Products {#applicable-products}
>
> * [Secure Card on File](https://developer.mastercard.com/mastercard-checkout-solutions/documentation/token-authentication/secure-card-on-file/index.md)   
> * [Click to Pay](https://developer.mastercard.com/mastercard-checkout-solutions/documentation/use-cases/click-to-pay/index.md)