OpenAI, proprietary

# GPT-5.1-Codex-mini

> GPT-5.1-Codex-mini by OpenAI, released November 2025. 2 published benchmark results. API: $0.25 in / $2 out per M tokens. 400K context. Scores, sources and comparisons.
- Canonical page: https://noometry.com/models/gpt-5-1-codex-mini
- Last updated: 2026-10-10
- Title: GPT-5.1-Codex-mini Benchmarks, Price & Rank (October 2026)

GPT-5.1-Codex-mini by OpenAI has 2 published benchmark results on Noometry, not yet enough to be ranked. API pricing starts at $0.25 per million input tokens and $2 per million output tokens, with a 400K-token context window.

Last verified October 10, 2026

## Specifications

- **Noometry rank:** Unranked
- **Index score:** Not ranked
- **Evidence:** Sparse 2 results
- **Provider:** [OpenAI](https://noometry.com/providers/openai)
- **Released:** November 12, 2025
- **Weights:** Proprietary
- **Reasoning:** Yes
- **Context window:** 400K
- **Max output:** 128K
- **Input price:** $0.25 / M
- **Output price:** $2 / M
- **Blended price:** $0.69 / M
- **Output speed:** Not measured
- **Value:** Not ranked
- **Knowledge cutoff:** September 2024
- **Input:** text, image

## Category scores

Each category score combines every public result we have in that category.

GPT-5.1-Codex-mini category scores

1.  Coding 31.6
2.  Agentic & Tool Use 38.5
3.  303234363840

GPT-5.1-Codex-mini category ranks
| Category | Score | Rank | Results |
| --- | --- | --- | --- |
| [Coding](https://noometry.com/best/coding) | 31.6 | — | 1 |
| [Agentic & Tool Use](https://noometry.com/best/agentic) | 38.5 | — | 1 |

Sponsored placements are available on pages like this one. [Advertise on Noometry](https://noometry.com/advertise)

## Benchmark results

Every published result we track, with its source. Bold rows are the ones used for ranking; where several exist we prefer independent runs over self-reported numbers.

### Coding

GPT-5.1-Codex-mini Coding benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [LMArena WebDev](https://noometry.com/benchmarks/arena-webdev) | 1244 | #102 of 113, top 91% |  | [LMArena](https://lmarena.ai/leaderboard/webdev) | 2026-10-08 |

### Agentic & Tool Use

GPT-5.1-Codex-mini Agentic & Tool Use benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [Terminal-Bench](https://noometry.com/benchmarks/terminal-bench) | 61.6% | #12 of 41, top 30% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |

## API pricing by provider

GPT-5.1-Codex-mini API prices
| Route | Input $/M | Output $/M | Cached input $/M | Checked |
| --- | --- | --- | --- | --- |
| [azure](https://learn.microsoft.com/en-us/azure/ai-services/openai/concepts/models) | $0.25 | $2 | $0.025 | 2026-10-10 |
| [openrouter](https://openrouter.ai/openai/gpt-5.1-codex-mini) | $0.25 | $2 | $0.03 | 2026-10-10 |

[All OpenAI API prices →](https://noometry.com/llm-pricing/openai) [Estimate your cost →](https://noometry.com/tools/cost-calculator)

## Compare GPT-5.1-Codex-mini

-   [GPT-5.1-Codex-mini vs GPT-6 Astra](https://noometry.com/compare/gpt-5-1-codex-mini-vs-gpt-6-astra)
-   [GPT-5.1-Codex-mini vs Claude Fable 5.1](https://noometry.com/compare/claude-fable-5-1-vs-gpt-5-1-codex-mini)
-   [GPT-5.1-Codex-mini vs Claude Opus 5.5](https://noometry.com/compare/claude-opus-5-5-vs-gpt-5-1-codex-mini)
-   [GPT-5.1-Codex-mini vs Claude Opus 5](https://noometry.com/compare/claude-opus-5-vs-gpt-5-1-codex-mini)
-   [GPT-5.1-Codex-mini vs Claude Fable 5](https://noometry.com/compare/claude-fable-5-vs-gpt-5-1-codex-mini)
-   [GPT-5.1-Codex-mini vs GPT-6.1 Sol](https://noometry.com/compare/gpt-5-1-codex-mini-vs-gpt-6-1-sol)
-   [GPT-5.1-Codex-mini vs Gemini 3.8 Flash](https://noometry.com/compare/gemini-3-8-flash-vs-gpt-5-1-codex-mini)
-   [GPT-5.1-Codex-mini vs Kimi K3](https://noometry.com/compare/gpt-5-1-codex-mini-vs-kimi-k3)
-   [GPT-5.1-Codex-mini vs Grok 4.6](https://noometry.com/compare/gpt-5-1-codex-mini-vs-grok-4-6)
-   [GPT-5.1-Codex-mini vs Qwen3.8 Max](https://noometry.com/compare/gpt-5-1-codex-mini-vs-qwen3-8-max)
-   [GPT-5.1-Codex-mini vs GLM-5.3](https://noometry.com/compare/glm-5-3-vs-gpt-5-1-codex-mini)
-   [GPT-5.1-Codex-mini vs Muse Spark 1.3](https://noometry.com/compare/gpt-5-1-codex-mini-vs-muse-spark-1-3)
-   [GPT-5.1-Codex-mini vs DeepSeek V4 Pro](https://noometry.com/compare/deepseek-v4-pro-vs-gpt-5-1-codex-mini)
-   [GPT-5.1-Codex-mini vs MiMo-V2.6-Pro](https://noometry.com/compare/gpt-5-1-codex-mini-vs-mimo-v2-6-pro)

## Other OpenAI models

-   [GPT-6 Astra](https://noometry.com/models/gpt-6-astra)70.8
-   [GPT-6.1 Sol](https://noometry.com/models/gpt-6-1-sol)65.6
-   [GPT-5.6 Sol](https://noometry.com/models/gpt-5-6-sol)65.0
-   [GPT-5.5 Pro](https://noometry.com/models/gpt-5-5-pro)64.3
-   [GPT-5.5](https://noometry.com/models/gpt-5-5)63.4
-   [GPT-6 Sol](https://noometry.com/models/gpt-6-sol)61.8
-   [GPT-5.4](https://noometry.com/models/gpt-5-4)59.4
-   [GPT-5.6 Terra](https://noometry.com/models/gpt-5-6-terra)59.2

## Frequently asked questions

### How good is GPT-5.1-Codex-mini?

GPT-5.1-Codex-mini by OpenAI has 2 published benchmark results on Noometry, not yet enough to be ranked. API pricing starts at $0.25 per million input tokens and $2 per million output tokens, with a 400K-token context window.

### How much does GPT-5.1-Codex-mini cost?

GPT-5.1-Codex-mini costs $0.25 per million input tokens and $2 per million output tokens on azure, with cached input at $0.025.

### What is GPT-5.1-Codex-mini's context window?

GPT-5.1-Codex-mini accepts up to 400K tokens of input and can write up to 128K tokens in one response.

### Is GPT-5.1-Codex-mini open source?

No. GPT-5.1-Codex-mini is proprietary and available only through OpenAI's API and partner platforms.

### Cite this page

Noometry. (2026). GPT-5.1-Codex-mini benchmarks and pricing. Retrieved October 10, 2026, from https://noometry.com/models/gpt-5-1-codex-mini

Quote Noometry with a link back to this page. It is also available in [Markdown](https://noometry.com/md/models/gpt-5-1-codex-mini.md).