# Claude Sonnet 4.6 vs Step 3

> Claude Sonnet 4.6 is the stronger model overall, scoring 50.3 to 40.5 on the Noometry Index.

- Canonical page: https://noometry.com/compare/claude-sonnet-4-6-vs-step-3
- Last updated: 2026-10-11
- Shared benchmarks: 16

## Summary

- They share 16 benchmarks with published results for both. Claude Sonnet 4.6 scores higher in 9 categories and Step 3 in 0 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Claude Sonnet 4.6 leads 46.1 to 28.4.
- Step 3 has downloadable open weights; the other is API-only.

## Snapshot

| | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| Provider | Anthropic | StepFun |
| Noometry Index | 50.3 | 40.5 |
| Rank | 50 | 149 |
| Context | 1M | — |
| Input $/M | $3 | — |
| Output $/M | $15 | — |
| Weights | Proprietary | Open |

## Coding

- Claude Sonnet 4.6: 46.3 (#67)
- Step 3: 40.1 (#147)

| Benchmark | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| LMArena Coding | 1504 | 1367 |
| SWE-bench Verified | 75.2% | — |
| DeepSWE | 29.9% | — |
| FrontierCode | 24.3% | — |
| LMArena WebDev | 1522 | — |
| SciCode | 46.8% | — |
| WeirdML | 66.1% | — |
| ALE-Bench | 1,327 | — |

## Agentic & Tool Use

- Claude Sonnet 4.6: 39.1 (#28)
- Step 3: —

| Benchmark | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| Terminal-Bench | 53.4% | — |
| APEX-Agents | 43% | — |
| OSWorld 2.0 | 9.3% | — |
| DeepResearch Bench | 54.9% | — |
| OSWorld | 72.1% | — |
| ExploitBench | 23.6% | — |
| GBAEval | 48.8% | — |
| GDP.pdf | 18% | — |
| LMArena Search | 1221 | — |
| Vending-Bench 2 | 7,204 | — |

## Reasoning

- Claude Sonnet 4.6: 46.1 (#45)
- Step 3: 28.4 (#105)

| Benchmark | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| LMArena Hard Prompts | 1484 | 1355 |
| ARC-AGI-2 | 60.4% | — |
| Kagi LLM Benchmark | — | 62.3% |
| NYT Connections (extended) | 80.9% | — |
| ARC-AGI-1 | 86.5% | — |
| CritPt | 3.1% | — |
| Chess Puzzles | 13% | — |
| Thematic Generalization | 76.3% | — |
| Mystery Game Puzzles | 16% | — |
| DTBench | 89.9% | — |
| LMCA | 46.5% | — |
| Epoch Capabilities Index | 152.24 | — |
| ForecastBench | 62 | — |

## Math

- Claude Sonnet 4.6: 52.9 (#49)
- Step 3: 37.6 (#148)

| Benchmark | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| LMArena Math | 1462 | 1366 |
| OTIS Mock AIME 2024-2025 | 85.8% | — |
| ProofBench | 45% | — |
| FrontierMath (Feb 2025 set) | 32.4% | — |
| FrontierMath Tier 4 (v1) | 8.3% | — |

## Knowledge

- Claude Sonnet 4.6: 51.7 (#65)
- Step 3: 36.8 (#164)

| Benchmark | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| LMArena Expert | 1500 | 1333 |
| GPQA Diamond | 87.4% | — |
| SimpleQA Verified | 35.5% | — |
| Vectara Hallucination Rate | 10.6% | — |

## Multimodal

- Claude Sonnet 4.6: 38.0 (#68)
- Step 3: 35.5 (#86)

| Benchmark | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| LMArena Vision | 1283 | 1177 |
| Blueprint-Bench 2 | 6.7% | — |
| LMArena Document | 1482 | — |

## Multilingual

- Claude Sonnet 4.6: 54.4 (#41)
- Step 3: 46.3 (#159)

| Benchmark | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| LMArena Non-English | 1440 | 1327 |
| LMArena Chinese | 1491 | 1397 |
| LMArena German | 1428 | 1371 |
| LMArena Korean | 1411 | 1269 |
| LMArena Russian | 1440 | 1331 |
| LMArena Spanish | 1464 | 1371 |
| LMArena French | 1465 | — |
| LMArena Japanese | 1420 | — |

## Instruction Following

- Claude Sonnet 4.6: 77.4 (#25)
- Step 3: 70.4 (#164)

| Benchmark | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| LMArena Instruction Following | 1475 | 1332 |

## Long Context

- Claude Sonnet 4.6: 45.3 (#44)
- Step 3: 40.3 (#157)

| Benchmark | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| LMArena Longer Query | 1479 | 1326 |

## Writing & Preference

- Claude Sonnet 4.6: 70.2 (#22)
- Step 3: 54.3 (#151)

| Benchmark | Claude Sonnet 4.6 | Step 3 |
|---|---|---|
| LMArena Text | 1458 | 1350 |
| LMArena Creative Writing | 1435 | 1321 |
| LMArena Multi-Turn | 1464 | 1341 |
| EQ-Bench Creative Writing | 1810 | — |
| EQ-Bench 4 | 1207 | — |

## FAQ

### Is Claude Sonnet 4.6 better than Step 3?

Claude Sonnet 4.6 is the stronger model overall, scoring 50.3 to 40.5 on the Noometry Index.

### Is Claude Sonnet 4.6 or Step 3 better for coding?

Claude Sonnet 4.6 scores higher on coding benchmarks: 46.3 versus 40.1 in the Noometry coding category.

### How many benchmarks do Claude Sonnet 4.6 and Step 3 share?

16 benchmarks have published results for both models. Claude Sonnet 4.6 has 57 scored results on Noometry and Step 3 has 17.