# GPT-5.6 Sol vs Kimi K3

> GPT-5.6 Sol is the stronger model overall, scoring 64.4 to 59.5 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-5-6-sol-vs-kimi-k3
- Last updated: 2026-10-10
- Shared benchmarks: 51

## Summary

- They share 51 benchmarks with published results for both. GPT-5.6 Sol scores higher in 6 categories and Kimi K3 in 4 categories; 7 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where GPT-5.6 Sol leads 74.7 to 63.0.
- The biggest single-benchmark swing is FrontierMath Tier 4: 82.9% for GPT-5.6 Sol and 39% for Kimi K3.
- Kimi K3 is cheaper at $3 / $15 per million input/output tokens, against $4 / $20 for GPT-5.6 Sol.
- GPT-5.6 Sol accepts more context: 1.05M tokens versus 1.05M.
- Kimi K3 has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| Provider | OpenAI | Moonshot AI |
| Noometry Index | 64.4 | 59.5 |
| Rank | 6 | 12 |
| Context | 1.05M | 1.05M |
| Input $/M | $4 | $3 |
| Output $/M | $20 | $15 |
| Weights | Proprietary | Open |

## Coding

- GPT-5.6 Sol: 61.1 (#7)
- Kimi K3: 60.6 (#8)

| Benchmark | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| DeepSWE | 72.7% | 68.5% |
| FrontierCode | 47.5% | 44.2% |
| LMArena WebDev | 1619 | 1659 |
| FrontierSWE | 32.2% | 25.9% |
| SciCode | 57.1% | 59.5% |
| WeirdML | 89.4% | 82.6% |
| LMArena Coding | 1493 | 1509 |
| ALE-Bench | 2,177 | 1,524 |
| CursorBench | 41.7% | — |
| MirrorCode | 20% | — |

## Agentic & Tool Use

- GPT-5.6 Sol: 50.2 (#7)
- Kimi K3: 41.8 (#19)

| Benchmark | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| APEX-Agents | 51.4% | 50.6% |
| τ²-bench Banking | 46.9% | 37.1% |
| PostTrainBench | 36.2% | 32% |
| GBAEval | 52.6% | 48.3% |
| GDP.pdf | 30.7% | 19% |
| Vending-Bench 2 | 9,619 | 5,165 |
| OSWorld 2.0 | 27.3% | — |
| BALROG | 60% | — |
| LMArena Search | 1257 | — |

## Reasoning

- GPT-5.6 Sol: 74.7 (#6)
- Kimi K3: 63.0 (#15)

| Benchmark | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| ARC-AGI-2 | 92.5% | 60.4% |
| SimpleBench | 71.7% | 60.7% |
| NYT Connections (extended) | 93.8% | 93.6% |
| ARC-AGI-1 | 97.5% | 94.5% |
| CritPt | 32.3% | 23.4% |
| Chess Puzzles | 64% | 39% |
| LMArena Hard Prompts | 1481 | 1495 |
| Mystery Game Puzzles | 58% | 26% |
| DTBench | 96% | 91.2% |
| LMCA | 59.2% | 52.7% |
| Surface Evolver Bench | 93.1% | 95% |
| Epoch Capabilities Index | 161.99 | 157.68 |
| Kagi LLM Benchmark | 67% | — |
| EnigmaEval | 37.1% | — |
| EBR-Bench | 44.8% | — |
| Bench to the Future 3 | 0.14 | — |
| ForecastBench | — | 61.1 |

## Math

- GPT-5.6 Sol: 85.5 (#7)
- Kimi K3: 74.0 (#13)

| Benchmark | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| FrontierMath (Tiers 1-3) | 89.1% | 72.2% |
| FrontierMath Tier 4 | 82.9% | 39% |
| OTIS Mock AIME 2024-2025 | 100% | 97.2% |
| ProofBench | 83% | 87% |
| LMArena Math | 1472 | 1493 |
| MathArena Final-Answer Competitions | — | 87.8% |
| FrontierMath Erdős | 0% | — |

## Knowledge

- GPT-5.6 Sol: 64.3 (#16)
- Kimi K3: 63.2 (#19)

| Benchmark | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| GPQA Diamond | 93.5% | 93.1% |
| SimpleQA Verified | 69.7% | 50.6% |
| LMArena Expert | 1517 | 1520 |
| Vectara Hallucination Rate | 12.4% | — |

## Multimodal

- GPT-5.6 Sol: 48.9 (#8)
- Kimi K3: 38.4 (#58)

| Benchmark | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| Blueprint-Bench 2 | 33.6% | 29.5% |
| Furniture Assembly | 56.7% | 34.2% |
| LMArena Vision | 1281 | — |
| LMArena Document | 1483 | — |

## Multilingual

- GPT-5.6 Sol: 55.4 (#32)
- Kimi K3: 56.5 (#20)

| Benchmark | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| LMArena Non-English | 1450 | 1466 |
| LMArena Chinese | 1523 | 1528 |
| LMArena French | 1475 | 1488 |
| LMArena German | 1476 | 1474 |
| LMArena Japanese | 1475 | 1492 |
| LMArena Korean | 1434 | 1465 |
| LMArena Russian | 1466 | 1481 |
| LMArena Spanish | 1449 | 1478 |

## Instruction Following

- GPT-5.6 Sol: 77.8 (#16)
- Kimi K3: 77.8 (#13)

| Benchmark | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| LMArena Instruction Following | 1480 | 1481 |

## Long Context

- GPT-5.6 Sol: 45.3 (#42)
- Kimi K3: 45.8 (#27)

| Benchmark | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| LMArena Longer Query | 1479 | 1494 |

## Writing & Preference

- GPT-5.6 Sol: 73.5 (#12)
- Kimi K3: 76.7 (#4)

| Benchmark | GPT-5.6 Sol | Kimi K3 |
|---|---|---|
| LMArena Text | 1456 | 1476 |
| LMArena Creative Writing | 1450 | 1452 |
| EQ-Bench Creative Writing | 1972 | 2082 |
| EQ-Bench 4 | 1250 | 1339 |
| LMArena Multi-Turn | 1456 | 1488 |

## FAQ

### Is GPT-5.6 Sol better than Kimi K3?

GPT-5.6 Sol is the stronger model overall, scoring 64.4 to 59.5 on the Noometry Index.

### Which is cheaper, GPT-5.6 Sol or Kimi K3?

Kimi K3 is cheaper. It lists at $3 per million input tokens and $15 per million output tokens; GPT-5.6 Sol lists at $4 and $20.

### Is GPT-5.6 Sol or Kimi K3 better for coding?

They score almost the same on coding (61.1 vs 60.6); test both on your own repository before choosing.

### Which has the bigger context window?

GPT-5.6 Sol does, with 1.05M tokens against 1.05M.

### How many benchmarks do GPT-5.6 Sol and Kimi K3 share?

51 benchmarks have published results for both models. GPT-5.6 Sol has 64 scored results on Noometry and Kimi K3 has 53.