
GPT-5.1-Codex-Mini
GPT-5.1-Codex-Mini is a proprietary model from OpenAI, released Nov 13, 2025. It costs $0.25 per million input tokens and $2 per million output tokens, with a 400K-token context window.
- Developer
- OpenAI
- Released
- Nov 13, 2025
- Context window
- 400K
- Price in / out, per 1M tokens
- $0.25 / $2
- Weights
- Proprietary
- Inputs
- Images, Text
- Reasoning
- Yes
- Tool use
- Yes
LMArena, by category
| Leaderboard | Rating | Rank | Votes |
|---|---|---|---|
| WebDevLMArena | 1244 | 138 / 124 | 1.2K |
LMArena, CC BY 4.0, as of Oct 22, 2026. Where a model is rated at several effort levels, its best is shown.
Compare GPT-5.1-Codex-Mini
OpenAI
The lab behind GPT and ChatGPT, which brought large language models to hundreds of millions of people. Founded 2015, based in San Francisco. openai.com
Questions
Who makes GPT-5.1-Codex-Mini?
GPT-5.1-Codex-Mini is made by OpenAI, founded 2015 and based in San Francisco.
How much does GPT-5.1-Codex-Mini cost?
$0.25 per million input tokens and $2 per million output tokens, at its provider’s list price.
What is GPT-5.1-Codex-Mini’s context window?
400K tokens (400,000).
Is GPT-5.1-Codex-Mini open source?
No. GPT-5.1-Codex-Mini is proprietary and served through its provider’s API.
Gemini 4 Argon
Claude Opus 5.5
Muse Wonder
MiMo-V2.6-Pro
Qwen3.8-Max
Kimi K3
GLM-5.3
ERNIE 5.1
DeepSeek-V4.1-Flash-20260910
Grok 4.20 Beta
amazon-nova-experimental-chat
Dola Seed 2.0 Pro
NVIDIA-Nemotron-3-Ultra-550B-A55B
Gemma 4 31B
Step 5 Preview