# GPT-5.6 Sol vs Step 3

> GPT-5.6 Sol is the stronger model overall, scoring 65.0 to 40.5 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-5-6-sol-vs-step-3
- Last updated: 2026-10-11
- Shared benchmarks: 17

## Summary

- They share 17 benchmarks with published results for both. GPT-5.6 Sol scores higher in 9 categories and Step 3 in 0 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in math, where GPT-5.6 Sol leads 85.6 to 37.6.
- Step 3 has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-5.6 Sol | Step 3 |
|---|---|---|
| Provider | OpenAI | StepFun |
| Noometry Index | 65.0 | 40.5 |
| Rank | 7 | 149 |
| Context | 1.05M | — |
| Input $/M | $4 | — |
| Output $/M | $20 | — |
| Weights | Proprietary | Open |

## Coding

- GPT-5.6 Sol: 65.1 (#7)
- Step 3: 40.1 (#147)

| Benchmark | GPT-5.6 Sol | Step 3 |
|---|---|---|
| LMArena Coding | 1498 | 1367 |
| DeepSWE | 72.7% | — |
| FrontierCode | 47.5% | — |
| CursorBench | 41.7% | — |
| LMArena WebDev | 1618 | — |
| FrontierSWE | 32.2% | — |
| SciCode | 57.1% | — |
| GSO | 76.5% | — |
| WeirdML | 89.4% | — |
| MirrorCode | 20% | — |
| ALE-Bench | 2,177 | — |

## Agentic & Tool Use

- GPT-5.6 Sol: 50.3 (#7)
- Step 3: —

| Benchmark | GPT-5.6 Sol | Step 3 |
|---|---|---|
| APEX-Agents | 51.4% | — |
| OSWorld 2.0 | 27.3% | — |
| τ²-bench Banking | 46.9% | — |
| PostTrainBench | 36.2% | — |
| BALROG | 60% | — |
| GBAEval | 52.6% | — |
| GDP.pdf | 30.7% | — |
| LMArena Search | 1257 | — |
| Vending-Bench 2 | 9,619 | — |

## Reasoning

- GPT-5.6 Sol: 74.8 (#8)
- Step 3: 28.4 (#105)

| Benchmark | GPT-5.6 Sol | Step 3 |
|---|---|---|
| Kagi LLM Benchmark | 67% | 62.3% |
| LMArena Hard Prompts | 1484 | 1355 |
| ARC-AGI-2 | 92.5% | — |
| SimpleBench | 71.7% | — |
| NYT Connections (extended) | 93.8% | — |
| ARC-AGI-1 | 97.5% | — |
| CritPt | 32.3% | — |
| Chess Puzzles | 64% | — |
| EnigmaEval | 37.1% | — |
| EBR-Bench | 44.8% | — |
| Mystery Game Puzzles | 58% | — |
| DTBench | 96% | — |
| LMCA | 59.2% | — |
| Surface Evolver Bench | 93.1% | — |
| Bench to the Future 3 | 0.14 | — |
| Epoch Capabilities Index | 161.66 | — |

## Math

- GPT-5.6 Sol: 85.6 (#9)
- Step 3: 37.6 (#148)

| Benchmark | GPT-5.6 Sol | Step 3 |
|---|---|---|
| LMArena Math | 1474 | 1366 |
| FrontierMath (Tiers 1-3) | 89.1% | — |
| FrontierMath Tier 4 | 82.9% | — |
| OTIS Mock AIME 2024-2025 | 100% | — |
| ProofBench | 83% | — |
| FrontierMath Erdős | 0% | — |

## Knowledge

- GPT-5.6 Sol: 64.3 (#18)
- Step 3: 36.8 (#164)

| Benchmark | GPT-5.6 Sol | Step 3 |
|---|---|---|
| LMArena Expert | 1516 | 1333 |
| GPQA Diamond | 93.5% | — |
| SimpleQA Verified | 69.7% | — |
| Vectara Hallucination Rate | 12.4% | — |

## Multimodal

- GPT-5.6 Sol: 48.6 (#9)
- Step 3: 35.5 (#86)

| Benchmark | GPT-5.6 Sol | Step 3 |
|---|---|---|
| LMArena Vision | 1281 | 1177 |
| Blueprint-Bench 2 | 33.6% | — |
| Furniture Assembly | 56.7% | — |
| LMArena Document | 1483 | — |

## Multilingual

- GPT-5.6 Sol: 55.3 (#32)
- Step 3: 46.3 (#159)

| Benchmark | GPT-5.6 Sol | Step 3 |
|---|---|---|
| LMArena Non-English | 1452 | 1327 |
| LMArena Chinese | 1527 | 1397 |
| LMArena German | 1476 | 1371 |
| LMArena Korean | 1442 | 1269 |
| LMArena Russian | 1468 | 1331 |
| LMArena Spanish | 1441 | 1371 |
| LMArena French | 1477 | — |
| LMArena Japanese | 1471 | — |

## Instruction Following

- GPT-5.6 Sol: 77.7 (#16)
- Step 3: 70.4 (#164)

| Benchmark | GPT-5.6 Sol | Step 3 |
|---|---|---|
| LMArena Instruction Following | 1482 | 1332 |

## Long Context

- GPT-5.6 Sol: 45.4 (#42)
- Step 3: 40.3 (#157)

| Benchmark | GPT-5.6 Sol | Step 3 |
|---|---|---|
| LMArena Longer Query | 1480 | 1326 |

## Writing & Preference

- GPT-5.6 Sol: 73.3 (#12)
- Step 3: 54.3 (#151)

| Benchmark | GPT-5.6 Sol | Step 3 |
|---|---|---|
| LMArena Text | 1457 | 1350 |
| LMArena Creative Writing | 1448 | 1321 |
| LMArena Multi-Turn | 1460 | 1341 |
| EQ-Bench Creative Writing | 1972 | — |
| EQ-Bench 4 | 1250 | — |

## FAQ

### Is GPT-5.6 Sol better than Step 3?

GPT-5.6 Sol is the stronger model overall, scoring 65.0 to 40.5 on the Noometry Index.

### Is GPT-5.6 Sol or Step 3 better for coding?

GPT-5.6 Sol scores higher on coding benchmarks: 65.1 versus 40.1 in the Noometry coding category.

### How many benchmarks do GPT-5.6 Sol and Step 3 share?

17 benchmarks have published results for both models. GPT-5.6 Sol has 65 scored results on Noometry and Step 3 has 17.