# Grok 4.3 vs Kimi K2.5 Instant

> Grok 4.3 and Kimi K2.5 Instant score almost the same on the Noometry Index (43.8 vs 43.6), so choose on price, context window or the category you care about most.

- Canonical page: https://noometry.com/compare/grok-4-3-vs-kimi-k2-5-instant
- Last updated: 2026-10-10
- Shared benchmarks: 18

## Summary

- They share 18 benchmarks with published results for both. Grok 4.3 scores higher in 3 categories and Kimi K2.5 Instant in 6 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in knowledge, where Grok 4.3 leads 52.5 to 40.2.
- Kimi K2.5 Instant has downloadable open weights; the other is API-only.

## Snapshot

| | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| Provider | xAI | Moonshot AI |
| Noometry Index | 43.8 | 43.6 |
| Rank | 86 | 89 |
| Context | 1M | — |
| Input $/M | $1.25 | — |
| Output $/M | $2.50 | — |
| Weights | Proprietary | Open |

## Coding

- Grok 4.3: 41.6 (#121)
- Kimi K2.5 Instant: 42.6 (#97)

| Benchmark | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena WebDev | 1357 | 1404 |
| LMArena Coding | 1415 | 1484 |
| SciCode | 47.3% | — |
| WeirdML | 49.9% | — |
| ALE-Bench | 944.17 | — |

## Agentic & Tool Use

- Grok 4.3: 27.7 (#99)
- Kimi K2.5 Instant: —

| Benchmark | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| GDP.pdf | 8% | — |
| LMArena Search | 1165 | — |
| Vending-Bench 2 | 35.26 | — |

## Reasoning

- Grok 4.3: 35.9 (#68)
- Kimi K2.5 Instant: 29.7 (#90)

| Benchmark | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Hard Prompts | 1396 | 1443 |
| NYT Connections (extended) | 55.2% | — |
| CritPt | 8% | — |
| Chess Puzzles | 25% | — |
| DTBench | 90.7% | — |
| LMCA | 38.3% | — |
| Epoch Capabilities Index | 149.16 | — |
| ForecastBench | 60.3 | — |

## Math

- Grok 4.3: 46.0 (#74)
- Kimi K2.5 Instant: 39.4 (#105)

| Benchmark | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Math | 1388 | 1442 |
| FrontierMath (Tiers 1-3) | 42.8% | — |
| FrontierMath Tier 4 | 14.6% | — |
| OTIS Mock AIME 2024-2025 | 93.3% | — |
| ProofBench | 11% | — |

## Knowledge

- Grok 4.3: 52.5 (#62)
- Kimi K2.5 Instant: 40.2 (#123)

| Benchmark | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Expert | 1385 | 1440 |
| GPQA Diamond | 88.8% | — |
| SimpleQA Verified | 33.2% | — |

## Multimodal

- Grok 4.3: 31.6 (#104)
- Kimi K2.5 Instant: 40.2 (#50)

| Benchmark | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Vision | 1229 | 1254 |
| Blueprint-Bench 2 | 0% | — |

## Multilingual

- Grok 4.3: 50.5 (#120)
- Kimi K2.5 Instant: 52.0 (#94)

| Benchmark | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Non-English | 1385 | 1406 |
| LMArena Chinese | 1422 | 1449 |
| LMArena French | 1412 | 1403 |
| LMArena German | 1395 | 1413 |
| LMArena Korean | 1356 | 1378 |
| LMArena Russian | 1399 | 1404 |
| LMArena Spanish | 1398 | 1447 |
| LMArena Japanese | 1379 | — |

## Instruction Following

- Grok 4.3: 72.1 (#140)
- Kimi K2.5 Instant: 75.3 (#65)

| Benchmark | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Instruction Following | 1366 | 1430 |

## Long Context

- Grok 4.3: 42.5 (#123)
- Kimi K2.5 Instant: 43.9 (#83)

| Benchmark | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Longer Query | 1393 | 1435 |

## Writing & Preference

- Grok 4.3: 58.5 (#118)
- Kimi K2.5 Instant: 60.6 (#95)

| Benchmark | Grok 4.3 | Kimi K2.5 Instant |
|---|---|---|
| LMArena Text | 1397 | 1420 |
| LMArena Creative Writing | 1380 | 1381 |
| LMArena Multi-Turn | 1406 | 1427 |
| EQ-Bench 4 | 1075 | — |

## FAQ

### Is Grok 4.3 better than Kimi K2.5 Instant?

Grok 4.3 and Kimi K2.5 Instant score almost the same on the Noometry Index (43.8 vs 43.6), so choose on price, context window or the category you care about most.

### Is Grok 4.3 or Kimi K2.5 Instant better for coding?

They score almost the same on coding (41.6 vs 42.6); test both on your own repository before choosing.

### How many benchmarks do Grok 4.3 and Kimi K2.5 Instant share?

18 benchmarks have published results for both models. Grok 4.3 has 40 scored results on Noometry and Kimi K2.5 Instant has 18.