OpenAI · Released Nov 13, 2025GPT-5.1
Sharper GPT-5 generation for coding, product work, and tool-assisted tasks.
- Capability
- 149.7ECI · #52 of 148
- Input
- $1.25per 1M tokens
- Output
- $10.00per 1M tokens
- Context
- 400K128K max output
What it costs
- Input
- $1.25per million tokens
- Output
- $10.00per million tokens
- Cached input
- $0.125per million tokens
- Blended (3:1)
- $3.44pricier than 78% of priced models
Typical monthly bills
| Monthly usage | Estimated cost |
|---|---|
| Side project2M input + 0.5M output tokens | $7.50 |
| Team assistant25M input + 5M output tokens | $81.25 |
| Production app250M input + 50M output tokens | $812.50 |
Official OpenAI API price, as listed on models.dev.
Independent benchmarks
#52 of 148 scored models
The shaded band is Epoch AI’s confidence range (148.3–151.1); the tick marks the median scored model.
Scores from Epoch AI, run independently of OpenAI.
The details
- Lab
- OpenAI
- Released
- Nov 13, 2025
- Knowledge cutoff
- Sep 30, 2024
- Context window
- 400,000 tokens
- Max output
- 128,000 tokens
- Inputs
- Text, Images
- Output
- Text
- Reasoning
- Adjustable effort low · medium · high
- Tool calling
- Yes
- Structured output
- Yes
- Weights
- Proprietary
- API model ID
gpt-5.1on OpenAI- Availability
- 21 API providerslisted on models.dev
More from OpenAI
About GPT-5.1
How much does GPT-5.1 cost?
GPT-5.1 costs $1.25 input / $10.00 output per million tokens (official OpenAI API price). Cached input is $0.125 per million tokens. At a 3:1 input-to-output mix that is $3.44 per million tokens, more expensive than 78% of the 360 priced models we track.
What is the context window of GPT-5.1?
GPT-5.1 accepts up to 400,000 tokens per request and can write up to 128,000 tokens in one response.
How good is GPT-5.1?
Epoch AI gives GPT-5.1 a Capabilities Index score of 149.7 (likely range 148.3–151.1), ranking it #52 of 148 models Epoch has scored. Epoch AI benchmark results: GPQA Diamond 87.6%, OTIS Mock AIME 2024–2025 88.6%, SWE-bench Verified 68.0%, SimpleQA Verified 48.0%.
Is GPT-5.1 open source?
No. GPT-5.1 is proprietary; you use it through OpenAI’s API or partner platforms.
What inputs does GPT-5.1 support?
GPT-5.1 accepts text and images and replies in text. It is a reasoning model with low, medium and high effort settings, supports tool calling and can return structured JSON output.
When was GPT-5.1 released?
OpenAI released GPT-5.1 on Nov 13, 2025. Its training data runs to Sep 30, 2024.
What are the best alternatives to GPT-5.1?
The closest current models from other labs on capability, price and release date are Qwen3.6 Max Preview (Alibaba (Qwen), ECI 149.2, $1.30 / $7.80), Gemini 3 Pro Preview (Google, ECI 153.0, $2.00 / $12.00), GLM-5.1 (Z.ai (Zhipu), ECI 149.9, $1.40 / $4.40) and Claude Opus 4.5 (Anthropic, ECI 150.1, $5.00 / $25.00).