# Claude Haiku 5.5 vs GPT-5.1-Codex-mini

> Claude Haiku 5.5 has enough public results to be ranked (#52); GPT-5.1-Codex-mini does not yet, so treat this comparison as directional.

- Canonical page: https://noometry.com/compare/claude-haiku-5-5-vs-gpt-5-1-codex-mini
- Last updated: 2026-10-12
- Shared benchmarks: 1

## Summary

- They share 1 benchmark with published results for both. Claude Haiku 5.5 scores higher in 1 category and GPT-5.1-Codex-mini in 0 categories; one gap is clear of the uncertainty.
- The widest gap is in coding, where Claude Haiku 5.5 leads 49.2 to 31.6.
- Claude Haiku 5.5 is cheaper at $0.10 / $0.50 per million input/output tokens, against $0.25 / $2 for GPT-5.1-Codex-mini.
- Claude Haiku 5.5 accepts more context: 1M tokens versus 400K.

## Snapshot

| | Claude Haiku 5.5 | GPT-5.1-Codex-mini |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Noometry Index | 49.5 | 37.3 |
| Rank | 52 | — |
| Context | 1M | 400K |
| Input $/M | $0.10 | $0.25 |
| Output $/M | $0.50 | $2 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Haiku 5.5: 49.2 (#50)
- GPT-5.1-Codex-mini: 31.6

| Benchmark | Claude Haiku 5.5 | GPT-5.1-Codex-mini |
|---|---|---|
| LMArena WebDev | 1587 | 1244 |

## Agentic & Tool Use

- Claude Haiku 5.5: —
- GPT-5.1-Codex-mini: 38.5

| Benchmark | Claude Haiku 5.5 | GPT-5.1-Codex-mini |
|---|---|---|
| Terminal-Bench | — | 61.6% |

## Reasoning

- Claude Haiku 5.5: 35.2 (#69)
- GPT-5.1-Codex-mini: —

| Benchmark | Claude Haiku 5.5 | GPT-5.1-Codex-mini |
|---|---|---|
| NYT Connections (extended) | 65.7% | — |
| Mystery Game Puzzles | 30% | — |

## Math

- Claude Haiku 5.5: 73.6 (#18)
- GPT-5.1-Codex-mini: —

| Benchmark | Claude Haiku 5.5 | GPT-5.1-Codex-mini |
|---|---|---|
| FrontierMath (Tiers 1-3) | 75.1% | — |
| FrontierMath Tier 4 | 46.3% | — |
| OTIS Mock AIME 2024-2025 | 98.9% | — |

## Knowledge

- Claude Haiku 5.5: 50.8 (#70)
- GPT-5.1-Codex-mini: —

| Benchmark | Claude Haiku 5.5 | GPT-5.1-Codex-mini |
|---|---|---|
| GPQA Diamond | 89.6% | — |
| SimpleQA Verified | 23.8% | — |

## Multimodal

- Claude Haiku 5.5: 43.7 (#21)
- GPT-5.1-Codex-mini: —

| Benchmark | Claude Haiku 5.5 | GPT-5.1-Codex-mini |
|---|---|---|
| Furniture Assembly | 47.5% | — |

## FAQ

### Is Claude Haiku 5.5 better than GPT-5.1-Codex-mini?

Claude Haiku 5.5 has enough public results to be ranked (#52); GPT-5.1-Codex-mini does not yet, so treat this comparison as directional.

### Which is cheaper, Claude Haiku 5.5 or GPT-5.1-Codex-mini?

Claude Haiku 5.5 is cheaper. It lists at $0.10 per million input tokens and $0.50 per million output tokens; GPT-5.1-Codex-mini lists at $0.25 and $2.

### Is Claude Haiku 5.5 or GPT-5.1-Codex-mini better for coding?

Claude Haiku 5.5 scores higher on coding benchmarks: 49.2 versus 31.6 in the Noometry coding category.

### Which has the bigger context window?

Claude Haiku 5.5 does, with 1M tokens against 400K.

### How many benchmarks do Claude Haiku 5.5 and GPT-5.1-Codex-mini share?

1 benchmark has published results for both models. Claude Haiku 5.5 has 9 scored results on Noometry and GPT-5.1-Codex-mini has 2.