OpenAI o1 and new tools for developers

Introducing OpenAI o1, Realtime API improvements, a new fine-tuning method and more for developers.

OpenAI

Introducing OpenAI o1, Realtime API improvements, a new fine-tuning method and more for developers.

Today we’re introducing more capable models, new tools for customization, and upgrades that improve performance, flexibility, and cost-efficiency for developers building with AI. This includes:

OpenAI o1, our reasoning model designed to handle complex multi-step tasks with advanced accuracy, is rolling out to developers on usage tier 5⁠(opens in a new window) in the API. o1 is the successor to OpenAI o1‑preview⁠, which developers have already used to build agentic applications to streamline customer support, optimize supply chain decisions, and forecast complex financial trends.

o1 is production-ready with key features to enable real-world use cases, including:

  • Function calling⁠(opens in a new window): Seamlessly connect o1 to external data and APIs.
  • Structured Outputs⁠(opens in a new window): Generate responses that reliably adhere to your custom JSON Schema.
  • Developer messages: Specify instructions or context for the model to follow, such as defining tone, style and other behavioral guidance.
  • Vision capabilities: Reason over images to unlock many more applications in science, manufacturing, or coding, where visual inputs matter.
  • Lower latency: o1 uses on average 60% fewer reasoning tokens than o1‑preview for a given request.
  • A new `reasoning_effort` API parameter allows you to control how long the model thinks before answering.

 

The snapshot of o1 we’re shipping today o1‑2024‑12‑17 is a new post-trained version of the model we released in ChatGPT two weeks ago. It improves on areas of model behavior based on feedback, while maintaining the frontier capabilities we evaluated in our o1 System Card.⁠ We’re also updating o1 in ChatGPT to this version soon. The evaluations we’re sharing below reflect the performance of this new snapshot, ensuring developers have up-to-date benchmarks for this version. 

o1‑2024‑12‑17 sets new state-of-the-art results on several benchmarks, improving cost-efficiency and performance.

Category Eval o1-2024-12-17 o1-preview
General GPQA diamond 75.7 73.3
MMLU (pass @1) 91.8 90.8
Coding SWE-bench Verified 48.9 41.3
LiveBench (Coding) 76.6 52.3
Math MATH (pass @1) 96.4 85.5
AIME 2024 (pass @1) 79.2 42.0
MGSM (pass @1) 89.3 90.8
Vision MMMU (pass @1) 77.3
MathVista (pass @1) 71.0
Factuality SimpleQA 42.6 42.4
Agents TAU-bench (retail) 73.5
TAU-bench (airline) 54.2

Accuracy

Additionally, we have observed that o1‑2024‑12‑17 significantly outperforms gpt-4o in our function calling and Structured Outputs testing.

The Realtime API⁠(opens in a new window) enables developers to create low-latency, natural conversational experiences. It’s ideal for voice assistants, live translation tools, virtual tutors, interactive customer support systems, or even your own virtual Santa⁠(opens in a new window). Today we’re releasing changes to address some of the most common requests from developers: a direct WebRTC integration, reduced pricing, and more control over responses.

We’re introducing WebRTC⁠(opens in a new window) support for the Realtime API. WebRTC is an open standard that makes it easier to build and scale real-time voice products across platforms—whether for browser-based apps, mobile clients, IoT devices, or direct server-to-server setups.

Our WebRTC integration is designed to enable smooth and responsive interactions in real-world conditions, even with variable network quality. It handles audio encoding, streaming, noise suppression, and congestion control. 

With WebRTC, you can now add Realtime capabilities with just a handful of lines of Javascript:

We’re releasing gpt-4o-realtime-preview-2024-12-17 as part of the Realtime API beta with improved voice quality, more reliable input (especially for dictated numbers), and reduced costs. Due to our efficiency improvements, we’re dropping the audio token price by 60% to $40/1M input tokens and $80/1M output tokens. Cached audio input costs are reduced by 87.5% to $2.50/1M input tokens.

We’re also bringing GPT‑4o mini to the Realtime API beta as gpt-4o-mini-realtime-preview-2024-12-17. GPT‑4o mini is our most cost-efficient small model and brings the same rich voice experiences to the Realtime API as GPT‑4o. GPT‑4o mini audio price is $10/1M input tokens and $20/1M output tokens. Text tokens are priced at $0.60/1M input tokens and $2.40/1M output tokens. Cached audio and text both cost $0.30/1M tokens. 

These snapshots are available in the Realtime API⁠(opens in a new window) and also in the Chat Completions API⁠(opens in a new window) as gpt-4o-audio-preview-2024-12-17 and gpt-4o-mini-audio-preview-2024-12-17.

The fine-tuning API now supports Preference Fine-Tuning⁠(opens in a new window) to make it easy to customize models based on user and developer preferences. This method uses Direct Preference Optimization (DPO)⁠(opens in a new window) to compare pairs of model responses, teaching the model to distinguish between preferred and non-preferred outputs. By learning from pairwise comparisons rather than fixed targets, Preference Fine-Tuning is especially effective for subjective tasks where tone, style, and creativity matter.

There are some key differences between Preference Fine-Tuning and Supervised Fine-Tuning, as shown below.

Supervised Fine-Tuning (SFT)

Preference Fine-Tuning (PFT)

Objective

Encourage the model to generate correct outputs by replicating labeled outputs

Optimize the model to favor desired behavior by reinforcing preferred responses and reducing the likelihood of unpreferred ones 

Training data

Exact input and output pairs

Pairs of preferred and non-preferred model output, via human annotation, A/B testing, or synthetic data generation

Use cases

Tasks where an ideal output is easy to prepare, such as custom code format, and strict correctness is needed

Effective for tasks where “better” responses are subjective, such as creative writing or summarization.

We started testing Preference Fine-Tuning with trusted partners who have seen promising results so far. For example, Rogo AI⁠(opens in a new window) is building an AI assistant for financial analysts that breaks down complex queries into sub-queries. Using their expert-built benchmark, Rogo-Golden, they found that while Supervised Fine-Tuning faced challenges with out-of-distribution query expansion—such as missing metrics like ARR for queries like “how fast is company X growing”—Preference Fine-Tuning resolved these issues, improving performance from 75% accuracy in the base model to over 80%.

Preference Fine-Tuning will roll out today for gpt-4o-2024-08-06 and will be available for gpt-4o-mini-2024-07-18 soon. It will be available at the same price per trained token as Supervised Fine-Tuning, with support for our newest models coming early next year. For more information, visit our fine-tuning guide⁠(opens in a new window) in the API documentation.

For more information on the Go SDK, check out the README on GitHub⁠(opens in a new window).

Java has been a staple of enterprise software development, favored for its type system and massive ecosystem of open-source libraries. The OpenAI Java SDK provides typed request and response objects, and helpful utilities to manage API requests.