# GPT-5-Codex vs o3-pro

> o3-pro is the stronger model overall, scoring 42.9 to 37.9 on the Noometry Index. GPT-5-Codex costs 10× less per token, which makes it the better buy when o3-pro's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-5-codex-vs-o3-pro
- Last updated: 2026-10-11
- Shared benchmarks: 2

## Summary

- They share 2 benchmarks with published results for both. GPT-5-Codex scores higher in 1 category and o3-pro in 1 category; 2 gaps are clear of the uncertainty.
- The widest gap is in coding, where o3-pro leads 55.5 to 42.4.
- GPT-5-Codex is cheaper at $1.25 / $10 per million input/output tokens, against $20 / $80 for o3-pro.
- GPT-5-Codex accepts more context: 400K tokens versus 200K.

## Snapshot

| | GPT-5-Codex | o3-pro |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Noometry Index | 37.9 | 42.9 |
| Rank | 192 | 105 |
| Context | 400K | 200K |
| Input $/M | $1.25 | $20 |
| Output $/M | $10 | $80 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5-Codex: 42.4 (#103)
- o3-pro: 55.5 (#24)

| Benchmark | GPT-5-Codex | o3-pro |
|---|---|---|
| WeirdML | 54.5% | 58.2% |
| Aider Polyglot | — | 84.9% |

## Agentic & Tool Use

- GPT-5-Codex: 31.0 (#72)
- o3-pro: —

| Benchmark | GPT-5-Codex | o3-pro |
|---|---|---|
| Terminal-Bench | 44.3% | — |

## Reasoning

- GPT-5-Codex: 30.9 (#83)
- o3-pro: 23.8 (#171)

| Benchmark | GPT-5-Codex | o3-pro |
|---|---|---|
| Kagi LLM Benchmark | 70.3% | 72.1% |
| ARC-AGI-2 | — | 4.9% |
| ARC-AGI-1 | — | 59.3% |
| DTBench | — | 86.9% |
| LMCA | — | 38.5% |
| Epoch Capabilities Index | — | 147.42 |

## Knowledge

- GPT-5-Codex: —
- o3-pro: 29.5 (#238)

| Benchmark | GPT-5-Codex | o3-pro |
|---|---|---|
| Confabulations | — | 14.2% |
| Vectara Hallucination Rate | — | 23.3% |

## Long Context

- GPT-5-Codex: —
- o3-pro: 72.2 (#1)

| Benchmark | GPT-5-Codex | o3-pro |
|---|---|---|
| Fiction.LiveBench | — | 97.2% |

## Writing & Preference

- GPT-5-Codex: —
- o3-pro: 57.1 (#133)

| Benchmark | GPT-5-Codex | o3-pro |
|---|---|---|
| Short-Story Creative Writing | — | 84.4% |

## FAQ

### Is GPT-5-Codex better than o3-pro?

o3-pro is the stronger model overall, scoring 42.9 to 37.9 on the Noometry Index. GPT-5-Codex costs 10× less per token, which makes it the better buy when o3-pro's lead doesn't matter for your workload.

### Which is cheaper, GPT-5-Codex or o3-pro?

GPT-5-Codex is cheaper. It lists at $1.25 per million input tokens and $10 per million output tokens; o3-pro lists at $20 and $80.

### Is GPT-5-Codex or o3-pro better for coding?

o3-pro scores higher on coding benchmarks: 55.5 versus 42.4 in the Noometry coding category.

### Which has the bigger context window?

GPT-5-Codex does, with 400K tokens against 200K.

### How many benchmarks do GPT-5-Codex and o3-pro share?

2 benchmarks have published results for both models. GPT-5-Codex has 3 scored results on Noometry and o3-pro has 12.