Obtaining Subscription Keys

Computer Vision services require special subscription keys. Every call to the Computer Vision API requires a subscription key. This key needs to be either passed through a query string parameter or specified in the request header.

To sign up for subscription keys, see Subscriptions. It's free to sign up. Pricing for these services is subject to change.


Your subscription keys are valid for only one of these Microsoft Azure Regions.

Region Address
West US westus.api.cognitive.microsoft.com
East US 2 eastus2.api.cognitive.microsoft.com
West Central US westcentralus.api.cognitive.microsoft.com
West Europe westeurope.api.cognitive.microsoft.com
Southeast Asia southeastasia.api.cognitive.microsoft.com

If you sign up using the Computer Vision free trial, your subscription keys are valid for the westcentral region (https://westcentralus.api.cognitive.microsoft.com/). That is the most common case. However, if you sign-up for Computer Vision with your Microsoft Azure account through the https://azure.microsoft.com/ website, you specify the region for your trial from the preceding list of regions.

For example, if you sign up for Computer Vision with your Microsoft Azure account and you specify westus for your region, you must use the westus region for your REST API calls (https://westus.api.cognitive.microsoft.com/).

If you forget the region for your subscription key after obtaining your trial key, you can find your region at https://azure.microsoft.com/try/cognitive-services/my-apis/.