**To update an API mapping** The following ``update-api-mapping`` example changes an API mapping for a custom domain name. As a result, the base URL using the custom domain name for the specified API and stage becomes ``https://api.example.com/dev``. :: aws apigatewayv2 update-api-mapping \ --api-id a1b2c3d4 \ --stage dev \ --domain-name api.example.com \ --api-mapping-id 0qzs2sy7bh \ --api-mapping-key dev Output:: { "ApiId": "a1b2c3d4", "ApiMappingId": "0qzs2sy7bh", "ApiMappingKey": "dev" "Stage": "dev" } For more information, see `Setting up a regional custom domain name in API Gateway <https://docs.aws.amazon.com/apigateway/latest/developerguide/apigateway-regional-api-custom-domain-create.html>`__ in the *Amazon API Gateway Developer Guide*.