# Claude Sonnet 5.5 vs GPT-5 Mini

> Claude Sonnet 5.5 is the stronger model overall, scoring 60.5 to 41.7 on the Noometry Index. GPT-5 Mini costs 5.8× less per token, which makes it the better buy when Claude Sonnet 5.5's lead doesn't matter for your workload.

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

## Summary

- They share 10 benchmarks with published results for both. Claude Sonnet 5.5 scores higher in 6 categories and GPT-5 Mini in 0 categories; 6 gaps are clear of the uncertainty.
- The widest gap is in math, where Claude Sonnet 5.5 leads 88.7 to 46.3.
- The biggest single-benchmark swing is ProofBench: 100% for Claude Sonnet 5.5 and 9% for GPT-5 Mini.
- GPT-5 Mini is cheaper at $0.25 / $2 per million input/output tokens, against $2 / $10 for Claude Sonnet 5.5.
- Claude Sonnet 5.5 accepts more context: 1M tokens versus 400K.

## Snapshot

| | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Noometry Index | 60.5 | 41.7 |
| Rank | 10 | 115 |
| Context | 1M | 400K |
| Input $/M | $2 | $0.25 |
| Output $/M | $10 | $2 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Sonnet 5.5: 65.5 (#6)
- GPT-5 Mini: 40.0 (#134)

| Benchmark | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| SciCode | 61% | 39.2% |
| ALE-Bench | 1,819 | 799.77 |
| SWE-bench Verified | — | 64.7% |
| FrontierCode | 52.1% | — |
| SWE-bench Verified (bash only) | — | 59.8% |
| CursorBench | 55.5% | — |
| LMArena WebDev | 1699 | — |
| SWE-bench Multilingual | — | 39.7% |
| FrontierSWE | 61.9% | — |
| WeirdML | — | 52.7% |
| LMArena Coding | — | 1406 |
| AlgoTune | — | 1.38 |

## Agentic & Tool Use

- Claude Sonnet 5.5: 44.9 (#14)
- GPT-5 Mini: 31.0 (#64)

| Benchmark | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| Terminal-Bench | — | 34.8% |
| APEX-Agents | 75.5% | — |
| Berkeley Function Calling Leaderboard | — | 55.5% |
| Vending-Bench 2 | — | -31.18 |

## Reasoning

- Claude Sonnet 5.5: 52.4 (#29)
- GPT-5 Mini: 24.1 (#153)

| Benchmark | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| CritPt | 31.4% | 0% |
| Mystery Game Puzzles | 65% | 10% |
| ARC-AGI-2 | — | 4.4% |
| Kagi LLM Benchmark | — | 70.3% |
| ARC-AGI-1 | — | 54.3% |
| Chess Puzzles | — | 30% |
| EnigmaEval | — | 8.2% |
| LMArena Hard Prompts | — | 1380 |
| DTBench | — | 80.5% |
| LMCA | — | 34.2% |
| Epoch Capabilities Index | — | 145.51 |
| ForecastBench | — | 61 |

## Math

- Claude Sonnet 5.5: 88.7 (#4)
- GPT-5 Mini: 46.3 (#59)

| Benchmark | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| FrontierMath (Tiers 1-3) | 88.8% | 46.7% |
| FrontierMath Tier 4 | 80.5% | 12.2% |
| OTIS Mock AIME 2024-2025 | 100% | 86.7% |
| ProofBench | 100% | 9% |
| Omni-MATH | — | 72.2% |
| LMArena Math | — | 1377 |
| MATH Level 5 | — | 97.8% |
| FrontierMath (Feb 2025 set) | — | 27.2% |
| FrontierMath Tier 4 (v1) | — | 6.3% |

## Knowledge

- Claude Sonnet 5.5: 66.0 (#11)
- GPT-5 Mini: 45.5 (#80)

| Benchmark | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| GPQA Diamond | 95.6% | 75% |
| SimpleQA Verified | 46.5% | 21.6% |
| Humanity's Last Exam | — | 19.4% |
| MMLU-Pro | — | 83.5% |
| Confabulations | — | 13.3% |
| Vectara Hallucination Rate | — | 12.9% |
| GPQA (HELM) | — | 75.6% |
| LMArena Expert | — | 1377 |

## Multimodal

- Claude Sonnet 5.5: 53.2 (#5)
- GPT-5 Mini: 35.0 (#80)

| Benchmark | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| LMArena Vision | — | 1202 |
| VPCT | — | 40.2% |
| Furniture Assembly | 75% | — |

## Multilingual

- Claude Sonnet 5.5: —
- GPT-5 Mini: 49.1 (#131)

| Benchmark | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| LMArena Non-English | — | 1363 |
| LMArena Chinese | — | 1387 |
| LMArena French | — | 1385 |
| LMArena German | — | 1366 |
| LMArena Japanese | — | 1342 |
| LMArena Korean | — | 1306 |
| LMArena Russian | — | 1362 |
| LMArena Spanish | — | 1355 |

## Instruction Following

- Claude Sonnet 5.5: —
- GPT-5 Mini: 76.4 (#43)

| Benchmark | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| IFEval | — | 92.7% |
| LMArena Instruction Following | — | 1357 |

## Long Context

- Claude Sonnet 5.5: —
- GPT-5 Mini: 41.9 (#127)

| Benchmark | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| Fiction.LiveBench | — | 69.4% |
| LMArena Longer Query | — | 1355 |

## Writing & Preference

- Claude Sonnet 5.5: —
- GPT-5 Mini: 55.4 (#143)

| Benchmark | Claude Sonnet 5.5 | GPT-5 Mini |
|---|---|---|
| LMArena Text | — | 1373 |
| LMArena Creative Writing | — | 1325 |
| Short-Story Creative Writing | — | 83.1% |
| EQ-Bench Creative Writing | — | 1313 |
| WildBench | — | 85.5% |
| LMArena Multi-Turn | — | 1363 |

## FAQ

### Is Claude Sonnet 5.5 better than GPT-5 Mini?

Claude Sonnet 5.5 is the stronger model overall, scoring 60.5 to 41.7 on the Noometry Index. GPT-5 Mini costs 5.8× less per token, which makes it the better buy when Claude Sonnet 5.5's lead doesn't matter for your workload.

### Which is cheaper, Claude Sonnet 5.5 or GPT-5 Mini?

GPT-5 Mini is cheaper. It lists at $0.25 per million input tokens and $2 per million output tokens; Claude Sonnet 5.5 lists at $2 and $10.

### Is Claude Sonnet 5.5 or GPT-5 Mini better for coding?

Claude Sonnet 5.5 scores higher on coding benchmarks: 65.5 versus 40.0 in the Noometry coding category.

### Which has the bigger context window?

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

### How many benchmarks do Claude Sonnet 5.5 and GPT-5 Mini share?

10 benchmarks have published results for both models. Claude Sonnet 5.5 has 16 scored results on Noometry and GPT-5 Mini has 60.