GPT-5.1-Codex
openai/gpt-5.1-codex-20251113
OpenAI's GPT-5.1-Codex, released on 2025-01-01, accepts text and image inputs and generates text output. It supports tool use and reasoning, has a context length of 400 000 tokens, and its weights are not open. Pricing is $1.25 per million input tokens and $10 per million output tokens.
- tool use
- structured outputs
- reasoning
At a glance
provideropenai
releasedJan 1, 2025
context400K
input / M$1.25
Specifications
What the API gives you
- Context window
- 400K tokens
- Max output
- 128K tokens
- Input price
- $1.25 / 1M tokens
- Output price
- $10 / 1M tokens
- Cache read
- $0.13 / 1M tokens
- Modalities
- text, image → text
- Knowledge cutoff
- —
- Released
- Jan 1, 2025
Recommendation coverage
Where this model appears
Not currently included in a published recommendation. This means the available task-specific evidence did not support a ranking yet—not that the model was reviewed and rejected.
Measured evidence
Public benchmark record
- LMArena WebDev
- 1330 Elo2026-07-16
- LMArena WebDev
- 1330 Elo2026-07-20
LMArena data licensed CC-BY-4.0. Aider (Apache-2.0) and SWE-bench (MIT) are open.
Catalog data via OpenRouter and models.dev. Last checked within the past 6 hours.