Get more users by offering one-click sign in for 500 million Office 365 and enterprise accounts

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Come as you are: we support iOS, Android, Windows, web. You bring your users and your stack, we shall make it work.

Build apps with Microsoft APIs

Access user data inside the enterprise– get an Office365 user’s calendar, mail and contacts. Perfect for viral growth.

Used by 85% of the Fortune 500

The Microsoft identity stack has been battle tested by the biggest companies in the world.

Hundreds of apps are using Microsoft Sign In, including

Be up and running in minutes

Select a platform for step-by-step instructions

Powerful identity features

Hybrid identity

Our login works across cloud and on-premises Active Directory, allowing users to sign in with their existing credentials.

Multi-factor Authentication

Ensuring customer security is critical, which is why AAD makes it easy to configure multi-factor authentication. If used by your customers, our SDKs automatically make your application compliant.

Enterprise Grade

Powerful, reliable and secure. We run a geo-replicated service with automatic failover so users can authenticate 24/7, with guaranteed 99.9% availability.

Single Sign On

We support seamless single sign on, so if you have multiple applications on the same device a user logging into one is automatically logged into the rest of your applications as well.


Need to support various platforms? We provide SDKs for all the popular technology stacks, including JavaScript, iOS and Android.

Microsoft APIs

Using our identity platform allows you to access a wealth of powerful data and functionality through the various Microsoft APIs, including Microsoft Graph, Azure AD Graph and the Skype API.

Industry Standard Protocols

We support OAuth 2.0, OpenID Connect, SAML 2.0 and WS-Federation 1.2. In addition, since we are standards compliant you can choose to code against the protocol directly.

Cross Platform

We provide a consistent experience across multiple form factors and multiple operating systems including iOS and Android, so your customers can continue using the devices they love.

Roll out the welcome mat to 85% of Fortune 500 employees with just a few lines of code