# How can I look up used email address? **URL:** \ **Category:** Get Help\ **Tags:** api, authentication-api, management-api\ **Created:** [March 29, 2022, 1:40pm UTC](https://community.auth0.com/t/how-can-i-look-up-used-email-address/80706 "2022-03-29T13:40:22Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![kwst](https://sea1.discourse-cdn.com/auth0/user_avatar/community.auth0.com/kwst/32/36162_2.png) [@kwst](https://community.auth0.com/u/kwst)\ **Post date:** [March 29, 2022, 1:40pm UTC](https://community.auth0.com/t/how-can-i-look-up-used-email-address/80706/1 "2022-03-29T13:40:22Z")
Hi. I’d like to know if the email address is used already. Is there such a API? When the user accesses signup page, if the email address is used already, I want to redirect to login page. I found `get_users_by_email` in management API. I can get user information by using this API. > **[Auth0 Management API v2](https://auth0.com/docs/api/management/v2#!/Users_By_Email/get_users_by_email)** And I found `GET /userinfo` API in authentication API. But this API needs access\_token. [https://auth0.com/docs/api/authentication#user-profile](https://auth0.com/docs/api/authentication#user-profile) I’d like to know API returns only whether the email exists or not. And I want the API not to need access\_token. Thanks. ---
**Author:** ![dan.woda](https://sea1.discourse-cdn.com/auth0/user_avatar/community.auth0.com/dan.woda/32/18340_2.png) [@dan.woda](https://community.auth0.com/u/dan.woda)\ **Post date:** [March 30, 2022, 3:02pm UTC](https://community.auth0.com/t/how-can-i-look-up-used-email-address/80706/3 "2022-03-30T15:02:47Z")
@kwst, This type of endpoint does not exist. Generally, checking user data without any form of auth (no token) can result in user enumeration and isn’t allowed. ---
**Author:** ![dan.woda](https://sea1.discourse-cdn.com/auth0/user_avatar/community.auth0.com/dan.woda/32/18340_2.png) [@dan.woda](https://community.auth0.com/u/dan.woda)\ **Post date:** [April 21, 2022, 11:58pm UTC](https://community.auth0.com/t/how-can-i-look-up-used-email-address/80706/4 "2022-04-21T23:58:38Z")