# GPT-5.4 nano vs GPT-5-Codex

> GPT-5.4 nano is the stronger model overall, scoring 41.9 to 37.3 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-5-4-nano-vs-gpt-5-codex
- Last updated: 2026-10-10
- Shared benchmarks: 2

## Summary

- They share 2 benchmarks with published results for both. GPT-5.4 nano scores higher in 1 category and GPT-5-Codex in 1 category; 2 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where GPT-5-Codex leads 30.0 to 23.8.
- The biggest single-benchmark swing is Kagi LLM Benchmark: 39.7% for GPT-5.4 nano and 70.3% for GPT-5-Codex.
- GPT-5.4 nano is cheaper at $0.20 / $1.25 per million input/output tokens, against $1.25 / $10 for GPT-5-Codex.

## Snapshot

| | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Noometry Index | 41.9 | 37.3 |
| Rank | 111 | 190 |
| Context | 400K | 400K |
| Input $/M | $0.20 | $1.25 |
| Output $/M | $1.25 | $10 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5.4 nano: 43.1 (#82)
- GPT-5-Codex: 41.9 (#100)

| Benchmark | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| WeirdML | 49.2% | 54.5% |
| SciCode | 46.9% | — |
| LMArena Coding | 1404 | — |
| ALE-Bench | 1,005 | — |

## Agentic & Tool Use

- GPT-5.4 nano: —
- GPT-5-Codex: 30.8 (#66)

| Benchmark | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| Terminal-Bench | — | 44.3% |

## Reasoning

- GPT-5.4 nano: 23.8 (#159)
- GPT-5-Codex: 30.0 (#80)

| Benchmark | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| Kagi LLM Benchmark | 39.7% | 70.3% |
| ARC-AGI-2 | 5.7% | — |
| ARC-AGI-1 | 51.5% | — |
| CritPt | 9.3% | — |
| Chess Puzzles | 30% | — |
| LMArena Hard Prompts | 1380 | — |
| Mystery Game Puzzles | 9% | — |
| DTBench | 80.3% | — |
| LMCA | 36.9% | — |
| Epoch Capabilities Index | 145.78 | — |
| ForecastBench | 57.3 | — |

## Math

- GPT-5.4 nano: 40.7 (#76)
- GPT-5-Codex: —

| Benchmark | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| FrontierMath (Tiers 1-3) | 44.9% | — |
| FrontierMath Tier 4 | 12.2% | — |
| OTIS Mock AIME 2024-2025 | 87.8% | — |
| ProofBench | 5% | — |
| LMArena Math | 1406 | — |
| FrontierMath (Feb 2025 set) | 25.9% | — |
| FrontierMath Tier 4 (v1) | 6.3% | — |

## Knowledge

- GPT-5.4 nano: 41.8 (#94)
- GPT-5-Codex: —

| Benchmark | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| GPQA Diamond | 78.5% | — |
| SimpleQA Verified | 11.7% | — |
| Vectara Hallucination Rate | 3.1% | — |
| LMArena Expert | 1397 | — |

## Multimodal

- GPT-5.4 nano: 36.0 (#73)
- GPT-5-Codex: —

| Benchmark | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| LMArena Vision | 1196 | — |

## Multilingual

- GPT-5.4 nano: 48.8 (#136)
- GPT-5-Codex: —

| Benchmark | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| LMArena Non-English | 1359 | — |
| LMArena Chinese | 1391 | — |
| LMArena French | 1396 | — |
| LMArena German | 1368 | — |
| LMArena Japanese | 1342 | — |
| LMArena Korean | 1321 | — |
| LMArena Russian | 1363 | — |
| LMArena Spanish | 1368 | — |

## Instruction Following

- GPT-5.4 nano: 72.1 (#139)
- GPT-5-Codex: —

| Benchmark | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| LMArena Instruction Following | 1362 | — |

## Long Context

- GPT-5.4 nano: 41.6 (#131)
- GPT-5-Codex: —

| Benchmark | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| LMArena Longer Query | 1365 | — |

## Writing & Preference

- GPT-5.4 nano: 55.9 (#137)
- GPT-5-Codex: —

| Benchmark | GPT-5.4 nano | GPT-5-Codex |
|---|---|---|
| LMArena Text | 1372 | — |
| LMArena Creative Writing | 1313 | — |
| LMArena Multi-Turn | 1382 | — |

## FAQ

### Is GPT-5.4 nano better than GPT-5-Codex?

GPT-5.4 nano is the stronger model overall, scoring 41.9 to 37.3 on the Noometry Index.

### Which is cheaper, GPT-5.4 nano or GPT-5-Codex?

GPT-5.4 nano is cheaper. It lists at $0.20 per million input tokens and $1.25 per million output tokens; GPT-5-Codex lists at $1.25 and $10.

### Is GPT-5.4 nano or GPT-5-Codex better for coding?

GPT-5.4 nano scores higher on coding benchmarks: 43.1 versus 41.9 in the Noometry coding category.

### Which has the bigger context window?

Both accept 400K tokens.

### How many benchmarks do GPT-5.4 nano and GPT-5-Codex share?

2 benchmarks have published results for both models. GPT-5.4 nano has 40 scored results on Noometry and GPT-5-Codex has 3.