# Claude 3 Haiku vs GPT-5.3 Codex

> GPT-5.3 Codex is the stronger model overall, scoring 45.5 to 25.7 on the Noometry Index.

- Canonical page: https://noometry.com/compare/claude-3-haiku-vs-gpt-5-3-codex
- Last updated: 2026-10-10
- Shared benchmarks: 2

## Summary

- They share 2 benchmarks with published results for both. Claude 3 Haiku scores higher in 0 categories and GPT-5.3 Codex in 1 category; one gap is clear of the uncertainty.
- The widest gap is in coding, where GPT-5.3 Codex leads 48.5 to 26.1.
- The biggest single-benchmark swing is WeirdML: 9.8% for Claude 3 Haiku and 79.3% for GPT-5.3 Codex.

## Snapshot

| | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Noometry Index | 25.7 | 45.5 |
| Rank | 333 | 61 |
| Context | — | 400K |
| Input $/M | — | $1.75 |
| Output $/M | — | $14 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude 3 Haiku: 26.1 (#320)
- GPT-5.3 Codex: 48.5 (#51)

| Benchmark | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| WeirdML | 9.8% | 79.3% |
| SWE-bench Verified | — | 74.8% |
| LMArena WebDev | — | 1408 |
| BigCodeBench Instruct | 39.4% | — |
| LMArena Coding | 1199 | — |
| BigCodeBench Complete | 50.1% | — |
| CadEval | 12% | — |
| ALE-Bench | — | 1,655 |
| HumanEval+ | 68.9% | — |
| MBPP+ | 68.8% | — |

## Agentic & Tool Use

- Claude 3 Haiku: —
- GPT-5.3 Codex: 47.8 (#9)

| Benchmark | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| Terminal-Bench | — | 78.4% |
| METR Time Horizons | — | 74.5% |
| Vending-Bench 2 | — | 5,940 |

## Reasoning

- Claude 3 Haiku: 15.7 (#303)
- GPT-5.3 Codex: —

| Benchmark | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| Epoch Capabilities Index | 118.3 | 156.84 |
| Kagi LLM Benchmark | 34.2% | — |
| LMArena Hard Prompts | 1174 | — |
| DTBench | 50.1% | — |
| LMCA | 8.8% | — |
| ForecastBench | 53.2 | — |
| WinoGrande | 74.2% | — |

## Math

- Claude 3 Haiku: 9.2 (#313)
- GPT-5.3 Codex: —

| Benchmark | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 1.8% | — |
| LMArena Math | 1188 | — |
| MATH Level 5 | 14.9% | — |

## Knowledge

- Claude 3 Haiku: 17.3 (#280)
- GPT-5.3 Codex: —

| Benchmark | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| GPQA Diamond | 36.3% | — |
| Confabulations | 34.2% | — |
| LMArena Expert | 1148 | — |
| MMLU | 73.8% | — |

## Multimodal

- Claude 3 Haiku: 23.1 (#123)
- GPT-5.3 Codex: —

| Benchmark | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| LMArena Vision | 950 | — |
| ScienceQA | 72% | — |

## Multilingual

- Claude 3 Haiku: 36.1 (#238)
- GPT-5.3 Codex: —

| Benchmark | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| LMArena Non-English | 1178 | — |
| LMArena Chinese | 1155 | — |
| LMArena French | 1194 | — |
| LMArena German | 1174 | — |
| LMArena Japanese | 1102 | — |
| LMArena Korean | 1108 | — |
| LMArena Russian | 1204 | — |
| LMArena Spanish | 1165 | — |

## Instruction Following

- Claude 3 Haiku: 61.5 (#242)
- GPT-5.3 Codex: —

| Benchmark | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| LMArena Instruction Following | 1174 | — |

## Long Context

- Claude 3 Haiku: 36.1 (#232)
- GPT-5.3 Codex: —

| Benchmark | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| LMArena Longer Query | 1191 | — |

## Writing & Preference

- Claude 3 Haiku: 29.8 (#286)
- GPT-5.3 Codex: —

| Benchmark | Claude 3 Haiku | GPT-5.3 Codex |
|---|---|---|
| LMArena Text | 1195 | — |
| LMArena Creative Writing | 1157 | — |
| EQ-Bench Creative Writing | 717 | — |
| LMArena Multi-Turn | 1190 | — |

## FAQ

### Is Claude 3 Haiku better than GPT-5.3 Codex?

GPT-5.3 Codex is the stronger model overall, scoring 45.5 to 25.7 on the Noometry Index.

### Is Claude 3 Haiku or GPT-5.3 Codex better for coding?

GPT-5.3 Codex scores higher on coding benchmarks: 48.5 versus 26.1 in the Noometry coding category.

### How many benchmarks do Claude 3 Haiku and GPT-5.3 Codex share?

2 benchmarks have published results for both models. Claude 3 Haiku has 37 scored results on Noometry and GPT-5.3 Codex has 8.