Since the publication of this blog post additional information has been released. To learn more please read Microsoft Cognitive Services – General availability for Face API, Computer Vision API and Content Moderator.

Good News – We've improved the Face APIs, Bad News – You'll need to update your code.

Today we introduced a new version of the Face APIs, still in public preview, which required a major version change from v0 to v1.0. Don’t worry, the existing v0 of the API is sticking around until 6/30/2016 to give time for everyone to migrate.If you are using Detection, Verification, or Grouping functionality, you’ll need to update from v0 to v1.0 in your code (or update to the latest package).If you are using persisted data, such as the identification functionality with Person Group and Person objects, then you’ll need to recreate and train those objects. This is a one-time change and future API updates will not impact persisted data.

Here are some upgrade notes on major changes you should be aware of, but be sure to check the v1.0 documentation for all the latest details.

Signature Changes
The root service endpoint has changed from to

There are also several signature changes for the methods, such as Face-Detect, Face-Identify, Face-Find Similar, Face-Group, so please see the v1.0 documentation for all the details.

We've made these changes to be more consistent in signature to other REST APIs from Microsoft, such as the new Microsoft Graph APIs.

Higher Call Limits
Based on community feedback we're raising the limits on many common API calls


New Limit

Group: Faces to be grouped

Now returns up to 1,000 candidates (previous limit was 100)

Find Similar: Candidate faces allowed

Now returns up to 1,000 candidates (previous limit was 100)

Person: Persisted faces per Person Object

Nowstore up to 248 per Person object (previous limit was 32)

New Feature: Face List
A recurring piece of feedback we heard was that Find Similar was painful to use with the 24hr FaceID expiration. We’re introducing a new API feature to address this, called Face Lists. With Face Lists, you can add multiple FaceIDs to a list which is persisted and use this Face List as a target for the Find-Similar API call. A face list holds a maximum of 1,000 faces.

Learn more here: Face-List: Add a Face

Updated NuGet Package
The version of the NuGet component Microsoft.ProjectOxford.Face has changed from 0.5.x to

To upgrade in Visual Studio:

  • Open your project consuming the Microsoft.ProjectOxford.Face package
  • In Visual Studio, go to this menu:
    • Tools > NuGet Package Manager > Manage NuGet Packages for Solution…
    • Select the package and choose from the version drop-down menu.
  • Explore


    Let us know what you think of Azure and what you would like to see in the future.


    Provide feedback

  • Build your cloud computing and Azure skills with free courses by Microsoft Learn.


    Explore Azure learning

Join the conversation

Leave a Reply

Your email address will not be published. Required fields are marked *