# Grok 3 vs Kimi K2.5 Instant

> Kimi K2.5 Instant is the stronger model overall, scoring 42.9 to 39.6 on the Noometry Index.

- Canonical page: https://noometry.com/compare/grok-3-vs-kimi-k2-5-instant
- Last updated: 2026-10-10
- Shared benchmarks: 16

## Summary

- They share 16 benchmarks with published results for both. Grok 3 scores higher in 2 categories and Kimi K2.5 Instant in 6 categories; 4 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Kimi K2.5 Instant leads 28.5 to 13.8.
- Kimi K2.5 Instant has downloadable open weights; the other is API-only.

## Snapshot

| | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| Provider | xAI | Moonshot AI |
| Noometry Index | 39.6 | 42.9 |
| Rank | 150 | 92 |
| Context | — | — |
| Input $/M | — | — |
| Output $/M | — | — |
| Weights | Proprietary | Open |

## Coding

- Grok 3: 41.5 (#113)
- Kimi K2.5 Instant: 42.3 (#95)

| Benchmark | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Coding | 1432 | 1483 |
| Aider Polyglot | 53.3% | — |
| LMArena WebDev | — | 1404 |
| WeirdML | 37.2% | — |

## Agentic & Tool Use

- Grok 3: 30.2 (#69)
- Kimi K2.5 Instant: —

| Benchmark | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| BALROG | 29.5% | — |

## Reasoning

- Grok 3: 13.8 (#322)
- Kimi K2.5 Instant: 28.5 (#88)

| Benchmark | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Hard Prompts | 1433 | 1443 |
| ARC-AGI-2 | 0% | — |
| SimpleBench | 36.1% | — |
| Kagi LLM Benchmark | 61.3% | — |
| ARC-AGI-1 | 5.5% | — |
| Epoch Capabilities Index | 138.34 | — |

## Math

- Grok 3: 36.2 (#122)
- Kimi K2.5 Instant: 36.6 (#105)

| Benchmark | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Math | 1390 | 1443 |
| OTIS Mock AIME 2024-2025 | 55.6% | — |
| Omni-MATH | 46.4% | — |
| MATH Level 5 | 88.7% | — |
| FrontierMath (Feb 2025 set) | 3.8% | — |
| FrontierMath Tier 4 (v1) | 0% | — |

## Knowledge

- Grok 3: 46.0 (#76)
- Kimi K2.5 Instant: 39.5 (#121)

| Benchmark | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Expert | 1420 | 1438 |
| GPQA Diamond | 75.8% | — |
| MMLU-Pro | 78.8% | — |
| Confabulations | 14.2% | — |
| Vectara Hallucination Rate | 5.8% | — |
| GPQA (HELM) | 65% | — |

## Multimodal

- Grok 3: —
- Kimi K2.5 Instant: 39.5 (#47)

| Benchmark | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Vision | — | 1254 |

## Multilingual

- Grok 3: 52.5 (#81)
- Kimi K2.5 Instant: 52.2 (#89)

| Benchmark | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Non-English | 1411 | 1406 |
| LMArena Chinese | 1448 | 1450 |
| LMArena French | 1460 | 1403 |
| LMArena German | 1431 | 1413 |
| LMArena Korean | 1374 | 1378 |
| LMArena Russian | 1416 | 1404 |
| LMArena Spanish | 1417 | 1448 |
| LMArena Japanese | 1389 | — |

## Instruction Following

- Grok 3: 75.2 (#69)
- Kimi K2.5 Instant: 75.5 (#61)

| Benchmark | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Instruction Following | 1409 | 1430 |
| IFEval | 88.4% | — |

## Long Context

- Grok 3: 38.7 (#187)
- Kimi K2.5 Instant: 43.8 (#82)

| Benchmark | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Longer Query | 1439 | 1435 |
| Fiction.LiveBench | 58.3% | — |

## Writing & Preference

- Grok 3: 56.0 (#136)
- Kimi K2.5 Instant: 60.8 (#91)

| Benchmark | Grok 3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Text | 1426 | 1420 |
| LMArena Creative Writing | 1414 | 1379 |
| LMArena Multi-Turn | 1424 | 1427 |
| Short-Story Creative Writing | 76.4% | — |
| EQ-Bench Creative Writing | 1186 | — |
| WildBench | 84.9% | — |

## FAQ

### Is Grok 3 better than Kimi K2.5 Instant?

Kimi K2.5 Instant is the stronger model overall, scoring 42.9 to 39.6 on the Noometry Index.

### Is Grok 3 or Kimi K2.5 Instant better for coding?

They score almost the same on coding (41.5 vs 42.3); test both on your own repository before choosing.

### How many benchmarks do Grok 3 and Kimi K2.5 Instant share?

16 benchmarks have published results for both models. Grok 3 has 40 scored results on Noometry and Kimi K2.5 Instant has 18.