Migrate from custom voice to custom neural voice


We are retiring the standard non-neural training tier of custom voice from March 1, 2021 through February 29, 2024. If you used a non-neural custom voice with your Speech resource prior to March 1, 2021 then you can continue to do so until February 29, 2024. All other Speech resources can only use custom neural voice. After February 29, 2024, the non-neural custom voices won't be supported with any Speech resource.

The custom neural voice lets you build higher-quality voice models while requiring less data. You can develop more realistic, natural, and conversational voices. Your customers and end users will benefit from the latest Text-to-Speech technology, in a responsible way.

Custom voice Custom neural voice
The standard, or "traditional," method of custom voice breaks down spoken language into phonetic snippets that can be remixed and matched using classical programming or statistical methods. Custom neural voice synthesizes speech using deep neural networks that have "learned" the way phonetics are combined in natural human speech rather than using classical programming or statistical methods.
Custom voice1 requires a large volume of voice data to produce a more human-like voice model. With fewer recorded lines, a standard custom voice model will tend to sound more obviously robotic. The custom neural voice capability enables you to create a unique brand voice in multiple languages and styles by using a small set of recordings.

1 When creating a custom voice model, the maximum number of data files allowed to be imported per subscription is 10 .zip files for free subscription (F0) users, and 500 for standard subscription (S0) users.

Action required

Before you can migrate to custom neural voice, your application must be accepted. Access to the custom neural voice service is subject to Microsoft's sole discretion based on our eligibility criteria. You must commit to using custom neural voice in alignment with our Responsible AI principles and the code of conduct.


Even without an Azure account, you can listen to voice samples in Speech Studio and determine the right voice for your business needs.

  1. Learn more about our policy on the limit access and then apply here.
  2. Once your application is approved, you will be provided with the access to the "neural" training feature. Make sure you log in to Speech Studio using the same Azure subscription that you provide in your application.
  3. Before you can train and deploy a custom voice model, you must create a voice talent profile. The profile requires an audio file recorded by the voice talent consenting to the usage of their speech data to train a custom voice model.
  4. Update your code in your apps if you have created a new endpoint with a new model.

Custom voice details (deprecated)

Read the following sections for details on custom voice.

Language support

Custom voice supports the following languages (locales).

Language Locale
Chinese (Mandarin, Simplified) zh-CN
Chinese (Mandarin, Simplified), English bilingual zh-CN bilingual
English (India) en-IN
English (United Kingdom) en-GB
English (United States) en-US
French (France) fr-FR
German (Germany) de-DE
Italian (Italy) it-IT
Portuguese (Brazil) pt-BR
Spanish (Mexico) es-MX

Regional support

If you've created a custom voice font, use the endpoint that you've created. You can also use the endpoints listed below, replacing the {deploymentId} with the deployment ID for your voice model.

Region Endpoint
Australia East https://australiaeast.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
Brazil South https://brazilsouth.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
Canada Central https://canadacentral.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
Central US https://centralus.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
East Asia https://eastasia.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
East US https://eastus.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
East US 2 https://eastus2.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
France Central https://francecentral.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
India Central https://centralindia.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
Japan East https://japaneast.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
Japan West https://japanwest.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
Korea Central https://koreacentral.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
North Central US https://northcentralus.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
North Europe https://northeurope.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
South Central US https://southcentralus.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
Southeast Asia https://southeastasia.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
UK South https://uksouth.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
West Europe https://westeurope.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
West Central US https://westcentralus.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
West US https://westus.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}
West US 2 https://westus2.voice.speech.microsoft.com/cognitiveservices/v1?deploymentId={deploymentId}

Next steps