---
stage: Create
group: Ecosystem
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
---
# GitLab as OpenID Connect identity provider **(FREE)**
This document is about using GitLab as an OpenID Connect identity provider
to sign in to other services.
## Introduction to OpenID Connect
[OpenID Connect](https://openid.net/connect/) \(OIDC) is a simple identity layer on top of the
OAuth 2.0 protocol. It allows clients to:
- Verify the identity of the end-user based on the authentication performed by GitLab.
- Obtain basic profile information about the end-user in an interoperable and REST-like manner.
OIDC performs many of the same tasks as OpenID 2.0, but is API-friendly and usable by native and
mobile applications.
On the client side, you can use [OmniAuth::OpenIDConnect](https://github.com/jjbohn/omniauth-openid-connect/) for Rails
applications, or any of the other available [client implementations](https://openid.net/developers/libraries/#connect).
The GitLab implementation uses the [doorkeeper-openid_connect](https://github.com/doorkeeper-gem/doorkeeper-openid_connect "Doorkeeper::OpenidConnect website") gem, refer
to its README for more details about which parts of the specifications
are supported.
## Enabling OpenID Connect for OAuth applications
Refer to the [OAuth guide](oauth_provider.md) for basic information on how to set up OAuth
applications in GitLab. To enable OIDC for an application, all you have to do
is select the `openid` scope in the application settings.
## Shared information
The following user information is shared with clients:
| Claim | Type | Description |
|:-----------------|:----------|:------------|
| `sub` | `string` | The ID of the user
| `sub_legacy` | `string` | An opaque token that uniquely identifies the user
**Deprecation notice:** this token isn't stable because it's tied to the Rails secret key base, and is provided only for migration to the new stable `sub` value available from GitLab 11.1
| `auth_time` | `integer` | The timestamp for the user's last authentication
| `name` | `string` | The user's full name
| `nickname` | `string` | The user's GitLab username
| `email` | `string` | The user's email address
This is the user's *primary* email address if the application has access to the `email` claim and the user's *public* email address otherwise
| `email_verified` | `boolean` | Whether the user's email address was verified
| `website` | `string` | URL for the user's website
| `profile` | `string` | URL for the user's GitLab profile
| `picture` | `string` | URL for the user's GitLab avatar
| `groups` | `array` | Names of the groups the user is a member of
The claims `sub`, `sub_legacy`, `email` and `email_verified` are included in the ID token, all other claims are available from the `/oauth/userinfo` endpoint used by OIDC clients.