# GPT-4.5 vs Kimi K3

> Kimi K3 is the stronger model overall, scoring 59.5 to 37.2 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-4-5-vs-kimi-k3
- Last updated: 2026-10-10
- Shared benchmarks: 25

## Summary

- They share 25 benchmarks with published results for both. GPT-4.5 scores higher in 0 categories and Kimi K3 in 10 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Kimi K3 leads 63.0 to 13.9.
- The biggest single-benchmark swing is ARC-AGI-1: 10.3% for GPT-4.5 and 94.5% for Kimi K3.
- Kimi K3 has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-4.5 | Kimi K3 |
|---|---|---|
| Provider | OpenAI | Moonshot AI |
| Noometry Index | 37.2 | 59.5 |
| Rank | 208 | 15 |
| Context | — | 1.05M |
| Input $/M | — | $3 |
| Output $/M | — | $15 |
| Weights | Proprietary | Open |

## Coding

- GPT-4.5: 42.2 (#109)
- Kimi K3: 61.0 (#10)

| Benchmark | GPT-4.5 | Kimi K3 |
|---|---|---|
| WeirdML | 39.4% | 82.6% |
| LMArena Coding | 1396 | 1508 |
| DeepSWE | — | 68.5% |
| FrontierCode | — | 44.2% |
| Aider Polyglot | 44.9% | — |
| LMArena WebDev | — | 1654 |
| FrontierSWE | — | 25.9% |
| SciCode | — | 59.5% |
| LiveBench Coding | 75.2% | — |
| ALE-Bench | — | 1,524 |

## Agentic & Tool Use

- GPT-4.5: 27.9 (#97)
- Kimi K3: 41.8 (#20)

| Benchmark | GPT-4.5 | Kimi K3 |
|---|---|---|
| APEX-Agents | — | 50.6% |
| τ²-bench Banking | — | 37.1% |
| Cybench | 17.5% | — |
| PostTrainBench | — | 32% |
| GBAEval | — | 48.3% |
| GDP.pdf | — | 19% |
| Vending-Bench 2 | — | 5,165 |

## Reasoning

- GPT-4.5: 13.9 (#330)
- Kimi K3: 63.0 (#17)

| Benchmark | GPT-4.5 | Kimi K3 |
|---|---|---|
| ARC-AGI-2 | 0.8% | 60.4% |
| SimpleBench | 34.5% | 60.7% |
| ARC-AGI-1 | 10.3% | 94.5% |
| LMArena Hard Prompts | 1403 | 1496 |
| Epoch Capabilities Index | 136.74 | 157.45 |
| ForecastBench | 61.7 | 61.1 |
| NYT Connections (extended) | — | 93.6% |
| CritPt | — | 23.4% |
| Chess Puzzles | — | 39% |
| EnigmaEval | 3.2% | — |
| LiveBench Reasoning | 71.1% | — |
| Mystery Game Puzzles | — | 26% |
| DTBench | — | 91.2% |
| LiveBench Data Analysis | 64.3% | — |
| LMCA | — | 52.7% |
| Surface Evolver Bench | — | 95% |
| LiveBench | 69% | — |

## Math

- GPT-4.5: 32.6 (#211)
- Kimi K3: 74.2 (#16)

| Benchmark | GPT-4.5 | Kimi K3 |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 37.8% | 97.2% |
| LMArena Math | 1412 | 1491 |
| FrontierMath (Tiers 1-3) | — | 72.2% |
| FrontierMath Tier 4 | — | 39% |
| MathArena Final-Answer Competitions | — | 87.8% |
| ProofBench | — | 87% |
| LiveBench Math | 69.3% | — |
| MATH Level 5 | 78.6% | — |

## Knowledge

- GPT-4.5: 32.5 (#211)
- Kimi K3: 63.2 (#21)

| Benchmark | GPT-4.5 | Kimi K3 |
|---|---|---|
| GPQA Diamond | 68.7% | 93.1% |
| LMArena Expert | 1394 | 1521 |
| Humanity's Last Exam | 5.4% | — |
| SimpleQA Verified | — | 50.6% |
| Confabulations | 13.6% | — |

## Multimodal

- GPT-4.5: 37.6 (#71)
- Kimi K3: 37.8 (#70)

| Benchmark | GPT-4.5 | Kimi K3 |
|---|---|---|
| LMArena Vision | 1195 | — |
| VPCT | 45% | — |
| Blueprint-Bench 2 | — | 29.5% |
| Furniture Assembly | — | 34.2% |

## Multilingual

- GPT-4.5: 52.5 (#83)
- Kimi K3: 56.3 (#21)

| Benchmark | GPT-4.5 | Kimi K3 |
|---|---|---|
| LMArena Non-English | 1413 | 1466 |
| LMArena Chinese | 1421 | 1529 |
| LMArena French | 1418 | 1491 |
| LMArena German | 1457 | 1488 |
| LMArena Japanese | 1416 | 1487 |
| LMArena Korean | 1392 | 1458 |
| LMArena Russian | 1419 | 1482 |
| LMArena Spanish | — | 1472 |

## Instruction Following

- GPT-4.5: 72.6 (#134)
- Kimi K3: 77.7 (#14)

| Benchmark | GPT-4.5 | Kimi K3 |
|---|---|---|
| LMArena Instruction Following | 1404 | 1483 |
| LiveBench Instruction Following | 72.3% | — |

## Long Context

- GPT-4.5: 40.4 (#155)
- Kimi K3: 45.8 (#29)

| Benchmark | GPT-4.5 | Kimi K3 |
|---|---|---|
| LMArena Longer Query | 1406 | 1494 |
| Fiction.LiveBench | 63.9% | — |

## Writing & Preference

- GPT-4.5: 56.9 (#134)
- Kimi K3: 76.6 (#4)

| Benchmark | GPT-4.5 | Kimi K3 |
|---|---|---|
| LMArena Text | 1417 | 1476 |
| LMArena Creative Writing | 1394 | 1454 |
| EQ-Bench Creative Writing | 1258 | 2082 |
| LMArena Multi-Turn | 1444 | 1488 |
| Short-Story Creative Writing | 75.6% | — |
| EQ-Bench 4 | — | 1339 |
| LiveBench Language | 61.5% | — |

## FAQ

### Is GPT-4.5 better than Kimi K3?

Kimi K3 is the stronger model overall, scoring 59.5 to 37.2 on the Noometry Index.

### Is GPT-4.5 or Kimi K3 better for coding?

Kimi K3 scores higher on coding benchmarks: 61.0 versus 42.2 in the Noometry coding category.

### How many benchmarks do GPT-4.5 and Kimi K3 share?

25 benchmarks have published results for both models. GPT-4.5 has 42 scored results on Noometry and Kimi K3 has 53.