GPT-5.1
GPT-5.1 is the latest frontier-grade model in the GPT-5 series, offering stronger general-purpose reasoning, improved instruction adherence, and a more natural conversational style compared to GPT-5. It uses adaptive reasoning to allocate computation dynamically, responding quickly to simple queries while spending more depth on complex tasks. The model produces clearer, more grounded explanations with reduced jargon, making it easier to follow even on technical or multi-step problems. Built for
Context window
This model accepts 272K tokens in one request (~204K words of text).
What fits in one request
- FitsShort documentAbout 1,500 words of text
- FitsLong documentAbout 37K words of text
- FitsSmall codebaseAbout 150K words of text
- Won't fitFull novelAbout 375K words of text
Specifications
Context size, pricing, and release info in one place.
- Context window
- 272,000 tokens (272K)
- Max output tokens
- 128,000 tokens (128K)
- Speed tier
- balanced
- Provider
- Openai
- Release date
- Nov 2025
- Input cost
- $1.38/M / 1M tokens
- Output cost
- $11.00/M / 1M tokens
- Cached input
- $0.140/M / 1M tokens
Capabilities
See which features this model supports, such as vision, tools, and streaming.
- Vision
- Accepts image inputs alongside text
- Supported
- Tool use
- Can call external tools and APIs
- Supported
- Function calling
- Structured function call interface
- Supported
- Extended thinking
- Shows its chain-of-thought reasoning
- Supported
- Streaming
- Returns tokens as they are generated
- Supported
- Prompt caching
- Reuse repeated prompt prefixes cheaply
- Supported
- Web search
- Can browse the web during a request
- Not supported
- Batch API
- Process many requests asynchronously
- Not supported
Best for
Jump to a guide or ranking that matches each workload.
Compare GPT-5.1
Open a side-by-side comparison with one click.
- GPT-5.1 vs Amazon Titan Text Express
GPT-5.1 has 547% larger context window
- GPT-5.1 vs Amazon Titan Text Lite
GPT-5.1 has 547% larger context window
- GPT-5.1 vs Amazon Titan Text Premier
GPT-5.1 has 547% larger context window
- GPT-5.1 vs Claude Instant
GPT-5.1 has 172% larger context window
- GPT-5.1 vs Anthropic Claude
GPT-5.1 has 172% larger context window
- GPT-5.1 vs Codellama 34b Instruct
GPT-5.1 has 6540% larger context window
Frequently asked questions
Short answers about context size and how this model behaves.
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