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We are thrilled to announce the availability of the latest iterations in the o-series of models: OpenAI o3 and o4-mini models on Microsoft Azure OpenAI Service in Azure AI Foundry and GitHub. These models represent a significant leap forward in AI reasoning, offering enhanced quality, safety, and performance compared to their predecessors.

Key features and enhancements

Both o3 and o4-mini offer significant improvements on quality and safety while supporting the existing features of o1 and o3-mini and delivering comparable or better performance through its integration and support of the newest APIs and reasoning features.

In addition, they introduce:

  • Multiple APIs support: Both models are available in Responses API and Chat Completions API with Responses API supporting seamless integration with multiple tools and enhanced transparency with the reasoning summary as part of the model output.
  • Reasoning summary: In the Responses API, both models now support reasoning summary in their output providing more insights into their thinking process. This enhances the explainability and the effectiveness of the resulting actions and tools that leverage the insights for even better outcomes.
  • Multimodality: With enhanced vision analysis capabilities in o3, and new vision support in o4-mini, both models expand their reasoning capabilities to process and analyze visual data, extracting valuable insights and generating comprehensive text outputs. This is supported in both Responses API and Chat Completions API.
  • Full tools support includes parallel tool calling: Both models are first reasoning models with full tools support like the mainline models including parallel tool calling. Customers can use these to build the next generation of agentic solutions. This capability is supported in both Responses API and Chat Completions API.

New innovations in safety

The o-series reasoning models use deliberative alignment, a training strategy that teaches reasoning models safety specifications and trains them to reason explicitly about these specifications before answering. Both o3 and o4-mini feature the next level of safety improvements within the o-series of models so you can use the power of these models knowing these models are pushing the frontiers on safety as well.

New audio models available 

Azure OpenAI Service has also introduced three powerful new audio models available for deployment today in East US2 on Azure AI Foundry: GPT-4o-Transcribe and GPT-4o-Mini-Transcribe, which are speech-to-text models outperforming previous benchmarks, and GPT-4o-Mini-TTS, a customizable text-to-speech model enabling detailed instructions on speech characteristics. Check out more on the Tech Community blog

A new era in AI reasoning

Imagine a world where AI reasoning is not just a tool but a partner in innovation. With the launch of o3 and o4-mini models, we are stepping into that world. These models are not just upgrades; they are gateways to new possibilities, enabling you to push the boundaries of what AI can achieve. Whether you’re solving complex problems, creating seamless workflows, or exploring new frontiers in AI, o3 and o4-mini are here to elevate your journey. Embrace the future of AI reasoning with Azure OpenAI Service and let your imagination soar. Sign up to use o3 and o4-mini in Azure AI Foundry today.

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