[Home](./index.md) > [@digitalpersona/authentication](./authentication.md) > [U2FAuth](./authentication.u2fauth.md) > [getAppId](./authentication.u2fauth.getappid.md) ## U2FAuth.getAppId() method Reads U2F AppID endpoint URL. Signature: ```typescript getAppId(): Promise; ``` Returns: `Promise` a promise to return a U2F AppID endpoint URL.