This article is to help you understand the support lifecycle for Azure OpenAI APIs.
Note
New API response objects may be added to the API response without version changes. We recommend you only parse the response objects you require.
The 2025-04-01-preview
Azure OpenAI spec uses OpenAPI 3.1, is a known issue that this is currently not fully supported by Azure API Management
API evolution
Historically, Azure OpenAI received monthly updates of new API versions. Taking advantage of new features required constantly updating code and environment variables with each new API release. Azure OpenAI also required the extra step of using Azure specific clients which created overhead when migrating code between OpenAI and Azure OpenAI. Starting in May 2025, you can now opt in to our next generation of v1 Azure OpenAI APIs which add support for:
- Ongoing access to the latest features with no need to update
api-version
each month. - OpenAI client support with minimal code changes to swap between OpenAI and Azure OpenAI when using key-based authentication.
For the initial preview launch we are only supporting a subset of the inference API. While in preview, operations may have incomplete functionality that will be continually expanded.
Code changes
Last generation API
import os
from openai import AzureOpenAI
client = AzureOpenAI(
api_key=os.getenv("AZURE_OPENAI_API_KEY"),
api_version="2025-04-01-preview",
azure_endpoint="https://YOUR-RESOURCE-NAME.openai.azure.com")
)
response = client.responses.create(
model="gpt-4.1-nano", # Replace with your model deployment name
input="This is a test."
)
print(response.model_dump_json(indent=2))
Next generation API
import os
from openai import OpenAI
client = OpenAI(
api_key=os.getenv("AZURE_OPENAI_API_KEY"),
base_url="https://YOUR-RESOURCE-NAME.openai.azure.com/openai/v1/",
default_query={"api-version": "preview"},
)
response = client.responses.create(
model="gpt-4.1-nano", # Replace with your model deployment name
input="This is a test.",
)
print(response.model_dump_json(indent=2))
OpenAI()
client is used instead ofAzureOpenAI()
.base_url
passes the Azure OpenAI endpoint and/openai/v1
is appended to the endpoint address.default_query={"api-version": "preview"}
indicates that the version-less always up-to-date preview API is being used.
Once we release the GA next generation v1 API, we will support two values: latest
and preview
. If api-version
is not passed traffic is automatically routed to the latest
GA version. Currently only preview
is supported.
Preview API releases
Azure OpenAI API latest releases:
- NEW v1 Preview API
- Inference: 2025-04-01-preview
- Authoring: 2025-04-01-preview
Changes between v1 preview release and 2025-04-01-preview
- v1 preview API
- Video generation support
- NEW Responses API features:
- Remote Model Context Protocol (MCP) servers tool integration
- Support for asynchronous background tasks
- Encrypted reasoning items
- Image generation
Changes between 2025-04-01-preview and 2025-03-01-preview
Changes between 2025-03-01-preview and 2025-02-01-preview
Changes between 2025-02-01-preview and 2025-01-01-preview
- Stored completions (distillation) API support.
Changes between 2025-01-01-preview and 2024-12-01-preview
prediction
parameter added for predicted outputs support.gpt-4o-audio-preview
model support.
Changes between 2024-12-01-preview and 2024-10-01-preview
store
, andmetadata
parameters added for stored completions support.reasoning_effort
added for latest reasoning models.user_security_context
added for Microsoft Defender for Cloud integration.
Changes between 2024-09-01-preview and 2024-08-01-preview
max_completion_tokens
added to supporto1-preview
ando1-mini
models.max_tokens
does not work with the o1 series models.parallel_tool_calls
added.completion_tokens_details
&reasoning_tokens
added.stream_options
&include_usage
added.
Changes between 2024-07-01-preview and 2024-08-01-preview API specification
- Structured outputs support.
- Large file upload API added.
- On your data changes:
- Mongo DB integration.
role_information
parameter removed.rerank_score
added to citation object.- AML datasource removed.
- AI Search vectorization integration improvements.
Changes between 2024-5-01-preview and 2024-07-01-preview API specification
- Batch API support added
- Vector store chunking strategy parameters
max_num_results
that the file search tool should output.
Changes between 2024-04-01-preview and 2024-05-01-preview API specification
- Assistants v2 support - File search tool and vector storage
- Fine-tuning checkpoints, seed, events
- On your data updates
- DALL-E 2 now supports model deployment and can be used with the latest preview API.
- Content filtering updates
Changes between 2024-03-01-preview and 2024-04-01-preview API specification
- Breaking Change: Enhancements parameters removed. This impacts the
gpt-4
Version:vision-preview
model. - timestamp_granularities parameter added.
audioWord
object added.- Additional TTS
response_formats: wav & pcm
.
Latest GA API release
Azure OpenAI API version 2024-10-21 is currently the latest GA API release. This API version is the replacement for the previous 2024-06-01
GA API release.
Updating API versions
We recommend first testing the upgrade to new API versions to confirm there's no impact to your application from the API update before making the change globally across your environment.
If you're using the OpenAI Python or JavaScript client libraries, or the REST API, you'll need to update your code directly to the latest preview API version.
If you're using one of the Azure OpenAI SDKs for C#, Go, or Java, you'll instead need to update to the latest version of the SDK. Each SDK release is hardcoded to work with specific versions of the Azure OpenAI API.