OpenAI, proprietary

# GPT-5.3 Codex

> GPT-5.3 Codex by OpenAI, released February 2026. Ranked #69 of 354 with a Noometry Index of 45.8. API: $1.75 in / $14 out per M tokens. 400K context. Scores, sources and comparisons.
- Canonical page: https://noometry.com/models/gpt-5-3-codex
- Last updated: 2026-10-10
- Title: GPT-5.3 Codex Benchmarks, Price & Rank (October 2026)

GPT-5.3 Codex by OpenAI ranks 69th of 354 ranked models on the Noometry Index as of October 2026, with a score of 45.8. Its strongest category is agentic & tool use, where it ranks 9th. API pricing starts at $1.75 per million input tokens and $14 per million output tokens, with a 400K-token context window.

Last verified October 10, 2026

## Specifications

- **Noometry rank:** #69 of 354
- **Index score:** 45.8
- **Evidence:** Reported 8 results
- **Provider:** [OpenAI](https://noometry.com/providers/openai)
- **Released:** February 5, 2026
- **Weights:** Proprietary
- **Reasoning:** Yes
- **Context window:** 400K
- **Max output:** 128K
- **Input price:** $1.75 / M
- **Output price:** $14 / M
- **Blended price:** $4.81 / M
- **Output speed:** Not measured
- **Value:** #186 of 219
- **Knowledge cutoff:** August 2025
- **Input:** text, image, pdf

## Category scores

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

GPT-5.3 Codex category scores

1.  Coding 48.6
2.  Agentic & Tool Use 48.0
3.  47.548.048.549.0

GPT-5.3 Codex category ranks
| Category | Score | Rank | Results |
| --- | --- | --- | --- |
| [Coding](https://noometry.com/best/coding) | 48.6 | #56 | 3 |
| [Agentic & Tool Use](https://noometry.com/best/agentic) | 48.0 | #9 | 1 |

## Strengths and weaknesses

Categories where GPT-5.3 Codex places highest and lowest among the models ranked in each, with its score against that category's median.

### Strongest categories

GPT-5.3 Codex: strongest categories
| Category | Score | vs median | Rank |
| --- | --- | --- | --- |
| [Agentic & Tool Use](https://noometry.com/best/agentic) | 48.0 | +17.7 | #9 of 154, top 6% |

### Weakest categories

GPT-5.3 Codex: weakest categories
| Category | Score | vs median | Rank |
| --- | --- | --- | --- |
| [Coding](https://noometry.com/best/coding) | 48.6 | +9.9 | #56 of 340, top 17% |

## Closest competitors

The models ranked just above and below GPT-5.3 Codex. When scores are this close, price and speed are often the better way to choose.

Models ranked closest to GPT-5.3 Codex
| Model | Rank | Score | Blended $/M | Speed |  |
| --- | --- | --- | --- | --- | --- |
| [Grok 4.20 Multi-Agent](https://noometry.com/models/grok-4-20-multi-agent) | #65 | 46.2 | $1.56 | — | [Compare](https://noometry.com/compare/gpt-5-3-codex-vs-grok-4-20-multi-agent) |
| [GLM-5](https://noometry.com/models/glm-5) | #66 | 46.1 | $1.55 | 23 | [Compare](https://noometry.com/compare/glm-5-vs-gpt-5-3-codex) |
| [Qwen3.5 397B-A17B](https://noometry.com/models/qwen3-5-397b-a17b) | #67 | 46.0 | $1.35 | 9 | [Compare](https://noometry.com/compare/gpt-5-3-codex-vs-qwen3-5-397b-a17b) |
| [Qwen3.8 27B](https://noometry.com/models/qwen3-8-27b) | #68 | 46.0 | $1.11 | — | [Compare](https://noometry.com/compare/gpt-5-3-codex-vs-qwen3-8-27b) |
| [Kimi K2 Thinking Turbo](https://noometry.com/models/kimi-k2-thinking-turbo) | #70 | 45.8 | — | — | [Compare](https://noometry.com/compare/gpt-5-3-codex-vs-kimi-k2-thinking-turbo) |
| [Qwen3.5 Max Preview](https://noometry.com/models/qwen3-5-max-preview) | #71 | 45.3 | — | — | [Compare](https://noometry.com/compare/gpt-5-3-codex-vs-qwen3-5-max-preview) |
| [Qwen3.7 Plus](https://noometry.com/models/qwen3-7-plus) | #72 | 45.3 | $0.70 | — | [Compare](https://noometry.com/compare/gpt-5-3-codex-vs-qwen3-7-plus) |
| [Hy4 preview](https://noometry.com/models/hy4-preview) | #73 | 45.3 | $1.13 | — | [Compare](https://noometry.com/compare/gpt-5-3-codex-vs-hy4-preview) |

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-5.3 Codex Coding benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [SWE-bench Verified](https://noometry.com/benchmarks/swe-bench-verified) | 74.8% | #15 of 32, top 47% | high | [Epoch AI](https://epoch.ai/benchmarks) | 2026-02-25 |
| [LMArena WebDev](https://noometry.com/benchmarks/arena-webdev) | 1409 | #69 of 113, top 62% |  | [LMArena](https://lmarena.ai/leaderboard/webdev) | 2026-10-08 |
| [WeirdML](https://noometry.com/benchmarks/weirdml) | 79.3% | #10 of 119, top 9% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |
| [WeirdML](https://noometry.com/benchmarks/weirdml) | 77.9% |  | xhigh | [Epoch AI](https://epoch.ai/benchmarks) |  |
| [ALE-Bench](https://noometry.com/benchmarks/ale-bench) | 1,655 | #12 of 105, top 12% | xhigh | [Epoch AI](https://epoch.ai/benchmarks) |  |

### Agentic & Tool Use

GPT-5.3 Codex Agentic & Tool Use benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [Terminal-Bench](https://noometry.com/benchmarks/terminal-bench) | 78.4% | #6 of 41, top 15% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |
| [METR Time Horizons](https://noometry.com/benchmarks/metr-time-horizons) | 74.5% | #6 of 32, top 19% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |
| [Vending-Bench 2](https://noometry.com/benchmarks/vending-bench-2) | 5,940 | #20 of 60, top 34% |  | [Epoch AI](https://epoch.ai/benchmarks) |  |

### Reasoning

GPT-5.3 Codex Reasoning benchmark results
| Benchmark | Score | Position | Setting | Source | Date |
| --- | --- | --- | --- | --- | --- |
| [Epoch Capabilities Index](https://noometry.com/benchmarks/epoch-capabilities-index) | 156.77 | #18 of 213, top 9% |  | [Epoch AI](https://epoch.ai/eci) | 2026-02-05 |

## API pricing by provider

GPT-5.3 Codex API prices
| Route | Input $/M | Output $/M | Cached input $/M | Checked |
| --- | --- | --- | --- | --- |
| [azure](https://learn.microsoft.com/en-us/azure/ai-services/openai/concepts/models) | $1.75 | $14 | $0.17 | 2026-10-10 |
| [openai](https://platform.openai.com/docs/models) | $1.75 | $14 | $0.17 | 2026-10-10 |
| [openrouter](https://openrouter.ai/openai/gpt-5.3-codex) | $1.75 | $14 | $0.17 | 2026-10-10 |

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

## Compare GPT-5.3 Codex

-   [GPT-5.3 Codex vs GPT-5.2 Codex](https://noometry.com/compare/gpt-5-2-codex-vs-gpt-5-3-codex)
-   [GPT-5.3 Codex vs Qwen3.8 27B](https://noometry.com/compare/gpt-5-3-codex-vs-qwen3-8-27b)
-   [GPT-5.3 Codex vs Kimi K2 Thinking Turbo](https://noometry.com/compare/gpt-5-3-codex-vs-kimi-k2-thinking-turbo)
-   [GPT-5.3 Codex vs Qwen3.5 397B-A17B](https://noometry.com/compare/gpt-5-3-codex-vs-qwen3-5-397b-a17b)
-   [GPT-5.3 Codex vs Qwen3.5 Max Preview](https://noometry.com/compare/gpt-5-3-codex-vs-qwen3-5-max-preview)
-   [GPT-5.3 Codex vs GLM-5](https://noometry.com/compare/glm-5-vs-gpt-5-3-codex)
-   [GPT-5.3 Codex vs Qwen3.7 Plus](https://noometry.com/compare/gpt-5-3-codex-vs-qwen3-7-plus)
-   [GPT-5.3 Codex vs Claude Fable 5.1](https://noometry.com/compare/claude-fable-5-1-vs-gpt-5-3-codex)
-   [GPT-5.3 Codex vs Gemini 3.8 Flash](https://noometry.com/compare/gemini-3-8-flash-vs-gpt-5-3-codex)
-   [GPT-5.3 Codex vs Kimi K3](https://noometry.com/compare/gpt-5-3-codex-vs-kimi-k3)
-   [GPT-5.3 Codex vs Grok 4.6](https://noometry.com/compare/gpt-5-3-codex-vs-grok-4-6)
-   [GPT-5.3 Codex vs Qwen3.8 Max](https://noometry.com/compare/gpt-5-3-codex-vs-qwen3-8-max)
-   [GPT-5.3 Codex vs GLM-5.3](https://noometry.com/compare/glm-5-3-vs-gpt-5-3-codex)
-   [GPT-5.3 Codex vs Muse Spark 1.3](https://noometry.com/compare/gpt-5-3-codex-vs-muse-spark-1-3)

## 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-5.3 Codex?

GPT-5.3 Codex by OpenAI ranks 69th of 354 ranked models on the Noometry Index as of October 2026, with a score of 45.8. Its strongest category is agentic & tool use, where it ranks 9th. API pricing starts at $1.75 per million input tokens and $14 per million output tokens, with a 400K-token context window.

### How much does GPT-5.3 Codex cost?

GPT-5.3 Codex costs $1.75 per million input tokens and $14 per million output tokens on OpenAI's own API, with cached input at $0.17.

### What is GPT-5.3 Codex's context window?

GPT-5.3 Codex accepts up to 400K tokens of input and can write up to 128K tokens in one response.

### Is GPT-5.3 Codex open source?

No. GPT-5.3 Codex is proprietary and available only through OpenAI's API and partner platforms.

### What are GPT-5.3 Codex's strengths and weaknesses?

Relative to other ranked models, GPT-5.3 Codex places best in agentic & tool use and lowest in coding.

### What is GPT-5.3 Codex best at?

Its best category is agentic & tool use, where it ranks 9th on Noometry.

### Cite this page

Noometry. (2026). GPT-5.3 Codex benchmarks and pricing. Retrieved October 10, 2026, from https://noometry.com/models/gpt-5-3-codex

Quote Noometry with a link back to this page. It is also available in [Markdown](https://noometry.com/md/models/gpt-5-3-codex.md).