OpenAI Releases o1-Pro: A New Model Designed for Advanced Reasoning

OpenAI has announced the release of o1-Pro, the latest addition to its O1 series of large language models. This release represents a significant development in AI technology, particularly in the domain of complex reasoning and problem-solving.

Technical Specifications and Capabilities

The o1-Pro model is part of OpenAI's O1 series, which are specifically trained using reinforcement learning techniques to improve reasoning capabilities. According to OpenAI's documentation, these models are designed to "think before they answer," allowing them to handle complex reasoning tasks more effectively than previous generations.

Key specifications of the o1-Pro model include:

• A 200,000 token context window, enabling the model to process extensive amounts of information
• Up to 100,000 maximum output tokens per response
• Knowledge cutoff date of October 1, 2023
• Specialized support for reasoning tokens

Availability and API Access

Unlike some of OpenAI's other models, o1-Pro is exclusively available through the Responses API. This specialized API is designed to support multi-turn model interactions, allowing the model to engage in more complex reasoning processes before generating its final response.

The model is not available through OpenAI's standard Chat Completions API, Assistants API, or other common endpoints, indicating its specialized nature and use cases.

Pricing Structure

OpenAI has implemented a token-based pricing model for o1-Pro, with distinct rates for input and output:

• Input: $150.00 per million tokens
• Output: $600.00 per million tokens

This pricing structure reflects the significantly higher computational resources required for the model compared to other offerings in OpenAI's lineup. For comparison:

• The standard o1 model costs $15.00 per million input tokens
• The o3-mini model costs $1.10 per million input tokens

Technical Features and Limitations

o1-Pro supports several advanced features, including:

• Function calling capabilities
• Structured output formatting
• Batch processing through the v1/batch endpoint

However, the model does not support several capabilities available in other OpenAI models:

• No support for streaming responses
• No fine-tuning capabilities
• No multimodal inputs beyond text and images (audio is not supported)
• Not available in the Assistants API or for real-time applications

Version Control Through Snapshots

OpenAI provides a snapshot system for o1-Pro that allows developers to lock in specific versions of the model, ensuring consistent performance and behavior over time. Currently available snapshots include:

• o1-Pro (default)
• o1-Pro-2025-03-19 (specific version)

Rate Limits and Usage Tiers

Access to o1-Pro is governed by rate limits that vary based on the user's usage tier. These limits control requests per minute (RPM), requests per day (RPD), and tokens per minute (TPM). As users increase their API usage and spending, these limits automatically adjust upward through five defined tiers.

The introduction of o1-Pro demonstrates OpenAI's continued focus on developing specialized AI systems with enhanced reasoning capabilities, particularly for applications requiring complex problem-solving and deep analysis of information.