# Grok 4 Fast vs Qwen3 8B

> Grok 4 Fast is the stronger model overall, scoring 39.0 to 33.3 on the Noometry Index.

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

## Summary

- They share 4 benchmarks with published results for both. Grok 4 Fast scores higher in 3 categories and Qwen3 8B in 3 categories; 5 gaps are clear of the uncertainty.
- The widest gap is in long context, where Grok 4 Fast leads 63.2 to 37.8.
- The biggest single-benchmark swing is Fiction.LiveBench: 94.4% for Grok 4 Fast and 62.1% for Qwen3 8B.
- Qwen3 8B has downloadable open weights; the other is API-only.

## Snapshot

| | Grok 4 Fast | Qwen3 8B |
|---|---|---|
| Provider | xAI | Alibaba (Qwen) |
| Noometry Index | 39.0 | 33.3 |
| Rank | 164 | 237 |
| Context | — | 131K |
| Input $/M | — | $0.18 |
| Output $/M | — | $0.70 |
| Weights | Proprietary | Open |

## Coding

- Grok 4 Fast: 32.3 (#264)
- Qwen3 8B: 33.4 (#245)

| Benchmark | Grok 4 Fast | Qwen3 8B |
|---|---|---|
| LMArena WebDev | 1160 | — |
| SciCode | — | 22.6% |
| WeirdML | 42.9% | — |
| LMArena Coding | 1429 | — |

## Agentic & Tool Use

- Grok 4 Fast: 29.3 (#80)
- Qwen3 8B: 29.9 (#71)

| Benchmark | Grok 4 Fast | Qwen3 8B |
|---|---|---|
| Berkeley Function Calling Leaderboard | — | 42.6% |
| τ²-bench Banking | 15.7% | — |
| Cybench | 30% | — |
| LMArena Search | 1171 | — |

## Reasoning

- Grok 4 Fast: 22.5 (#179)
- Qwen3 8B: 16.1 (#299)

| Benchmark | Grok 4 Fast | Qwen3 8B |
|---|---|---|
| DTBench | 82.7% | 59.7% |
| Epoch Capabilities Index | 144.21 | 136.17 |
| ARC-AGI-2 | 5.3% | — |
| Kagi LLM Benchmark | 66.1% | — |
| ARC-AGI-1 | 48.5% | — |
| CritPt | — | 0% |
| Chess Puzzles | — | 5% |
| LMArena Hard Prompts | 1413 | — |
| LMCA | — | 8.8% |
| ForecastBench | 60.5 | — |

## Math

- Grok 4 Fast: 36.1 (#126)
- Qwen3 8B: 33.3 (#176)

| Benchmark | Grok 4 Fast | Qwen3 8B |
|---|---|---|
| OTIS Mock AIME 2024-2025 | — | 56.1% |
| LMArena Math | 1419 | — |

## Knowledge

- Grok 4 Fast: 31.5 (#211)
- Qwen3 8B: 36.1 (#164)

| Benchmark | Grok 4 Fast | Qwen3 8B |
|---|---|---|
| Vectara Hallucination Rate | 19.7% | 4.8% |
| GPQA Diamond | — | 56.8% |
| LMArena Expert | 1411 | — |

## Multilingual

- Grok 4 Fast: 51.5 (#106)
- Qwen3 8B: —

| Benchmark | Grok 4 Fast | Qwen3 8B |
|---|---|---|
| LMArena Non-English | 1397 | — |
| LMArena Chinese | 1458 | — |
| LMArena French | 1433 | — |
| LMArena German | 1383 | — |
| LMArena Japanese | 1358 | — |
| LMArena Korean | 1359 | — |
| LMArena Russian | 1387 | — |
| LMArena Spanish | 1414 | — |

## Instruction Following

- Grok 4 Fast: 73.4 (#116)
- Qwen3 8B: —

| Benchmark | Grok 4 Fast | Qwen3 8B |
|---|---|---|
| LMArena Instruction Following | 1388 | — |

## Long Context

- Grok 4 Fast: 63.2 (#3)
- Qwen3 8B: 37.8 (#205)

| Benchmark | Grok 4 Fast | Qwen3 8B |
|---|---|---|
| Fiction.LiveBench | 94.4% | 62.1% |
| LMArena Longer Query | 1415 | — |

## Writing & Preference

- Grok 4 Fast: 60.2 (#96)
- Qwen3 8B: —

| Benchmark | Grok 4 Fast | Qwen3 8B |
|---|---|---|
| LMArena Text | 1407 | — |
| LMArena Creative Writing | 1388 | — |
| LMArena Multi-Turn | 1414 | — |

## FAQ

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

Grok 4 Fast is the stronger model overall, scoring 39.0 to 33.3 on the Noometry Index.

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

Qwen3 8B scores higher on coding benchmarks: 33.4 versus 32.3 in the Noometry coding category.

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

4 benchmarks have published results for both models. Grok 4 Fast has 30 scored results on Noometry and Qwen3 8B has 11.