# Grok 4 Fast vs Qwen3.8 27B

> Qwen3.8 27B is the stronger model overall, scoring 46.0 to 39.4 on the Noometry Index.

- Canonical page: https://noometry.com/compare/grok-4-fast-vs-qwen3-8-27b
- Last updated: 2026-10-10
- Shared benchmarks: 22

## Summary

- They share 22 benchmarks with published results for both. Grok 4 Fast scores higher in 2 categories and Qwen3.8 27B in 7 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in long context, where Grok 4 Fast leads 63.2 to 44.3.
- The biggest single-benchmark swing is ARC-AGI-1: 48.5% for Grok 4 Fast and 87.5% for Qwen3.8 27B.
- Qwen3.8 27B has downloadable open weights; the other is API-only.

## Snapshot

| | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| Provider | xAI | Alibaba (Qwen) |
| Noometry Index | 39.4 | 46.0 |
| Rank | 167 | 68 |
| Context | — | 262K |
| Input $/M | — | $0.99 |
| Output $/M | — | $1.49 |
| Weights | Proprietary | Open |

## Coding

- Grok 4 Fast: 32.5 (#271)
- Qwen3.8 27B: 50.5 (#44)

| Benchmark | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| LMArena WebDev | 1159 | 1593 |
| LMArena Coding | 1429 | 1482 |
| SciCode | — | 46.6% |
| WeirdML | 42.9% | — |

## Agentic & Tool Use

- Grok 4 Fast: 29.5 (#86)
- Qwen3.8 27B: 32.9 (#57)

| Benchmark | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| APEX-Agents | — | 47.5% |
| τ²-bench Banking | 15.7% | — |
| Cybench | 30% | — |
| LMArena Search | 1171 | — |

## Reasoning

- Grok 4 Fast: 22.2 (#201)
- Qwen3.8 27B: 41.0 (#54)

| Benchmark | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| ARC-AGI-2 | 5.3% | 42.4% |
| ARC-AGI-1 | 48.5% | 87.5% |
| LMArena Hard Prompts | 1412 | 1460 |
| DTBench | 82.7% | 88% |
| Epoch Capabilities Index | 144.2 | 149.38 |
| Kagi LLM Benchmark | 66.1% | — |
| NYT Connections (extended) | — | 54.5% |
| CritPt | — | 5.4% |
| LMCA | — | 41.4% |
| Surface Evolver Bench | — | 45% |
| ForecastBench | 60.5 | — |

## Math

- Grok 4 Fast: 38.9 (#123)
- Qwen3.8 27B: 37.1 (#161)

| Benchmark | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| LMArena Math | 1419 | 1456 |
| ProofBench | — | 16% |

## Knowledge

- Grok 4 Fast: 32.0 (#214)
- Qwen3.8 27B: 41.6 (#109)

| Benchmark | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| LMArena Expert | 1411 | 1482 |
| Vectara Hallucination Rate | 19.7% | — |

## Multimodal

- Grok 4 Fast: —
- Qwen3.8 27B: 41.3 (#37)

| Benchmark | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| LMArena Vision | — | 1271 |

## Multilingual

- Grok 4 Fast: 51.3 (#111)
- Qwen3.8 27B: 53.7 (#60)

| Benchmark | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| LMArena Non-English | 1396 | 1430 |
| LMArena Chinese | 1457 | 1504 |
| LMArena French | 1431 | 1465 |
| LMArena German | 1383 | 1438 |
| LMArena Japanese | 1352 | 1384 |
| LMArena Korean | 1357 | 1393 |
| LMArena Russian | 1389 | 1415 |
| LMArena Spanish | 1415 | 1448 |

## Instruction Following

- Grok 4 Fast: 73.2 (#121)
- Qwen3.8 27B: 75.8 (#53)

| Benchmark | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| LMArena Instruction Following | 1387 | 1439 |

## Long Context

- Grok 4 Fast: 63.2 (#3)
- Qwen3.8 27B: 44.3 (#70)

| Benchmark | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| LMArena Longer Query | 1415 | 1450 |
| Fiction.LiveBench | 94.4% | — |

## Writing & Preference

- Grok 4 Fast: 60.0 (#102)
- Qwen3.8 27B: 65.8 (#43)

| Benchmark | Grok 4 Fast | Qwen3.8 27B |
|---|---|---|
| LMArena Text | 1407 | 1441 |
| LMArena Creative Writing | 1387 | 1384 |
| LMArena Multi-Turn | 1414 | 1441 |
| EQ-Bench Creative Writing | — | 1671 |

## FAQ

### Is Grok 4 Fast better than Qwen3.8 27B?

Qwen3.8 27B is the stronger model overall, scoring 46.0 to 39.4 on the Noometry Index.

### Is Grok 4 Fast or Qwen3.8 27B better for coding?

Qwen3.8 27B scores higher on coding benchmarks: 50.5 versus 32.5 in the Noometry coding category.

### How many benchmarks do Grok 4 Fast and Qwen3.8 27B share?

22 benchmarks have published results for both models. Grok 4 Fast has 30 scored results on Noometry and Qwen3.8 27B has 31.