Context Window
Openaio1deepVision

o1-pro

The o1 series of models are trained with reinforcement learning to think before they answer and perform complex reasoning. The o1-pro model uses more compute to think harder and provide consistently better answers.

200K context·~150K words·100K max output
View context detailsCompare with Amazon Titan Text Express
Context window200Ktokens
Max output100Ktokens

Context window

This model accepts 200K tokens in one request (~150K words of text).

Context window size200K tokens
4K32K128K1M10M

What fits in one request

  • Short document
    About 1,500 words of text
    Fits
  • Long document
    About 37K words of text
    Fits
  • Small codebase
    About 150K words of text
    Fits
  • Full novel
    About 375K words of text
    Won't fit

Specifications

Context size, pricing, and release info in one place.

Context window
200,000 tokens (200K)
Max output tokens
100,000 tokens (100K)
Speed tier
deep
Provider
Openai
Model family
o1
Release date
Mar 2025

Capabilities

See which features this model supports, such as vision, tools, and streaming.

Supported (4)
Vision
Supported
Extended thinking
Supported
Streaming
Supported
Batch API
Supported
Not supported (4)
Tool use
Not supported
Function calling
Not supported
Web search
Not supported
Prompt caching
Not supported

Best for

Jump to a guide or ranking that matches each workload.

ReasoningMultimodalLong documentsRAG

Compare o1-pro

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Frequently asked questions

Short answers about context size and how this model behaves.

o1-pro has a context window of 200K tokens (200,000 tokens). This large window is well-suited for long document analysis, extensive codebases, and multi-session agent workflows.

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