# Grok-3 mini vs Grok 4 Fast

> Grok-3 mini is the stronger model overall, scoring 41.0 to 39.0 on the Noometry Index.

- Canonical page: https://noometry.com/compare/grok-3-mini-vs-grok-4-fast
- Last updated: 2026-10-10
- Shared benchmarks: 23

## Summary

- They share 23 benchmarks with published results for both. Grok-3 mini scores higher in 4 categories and Grok 4 Fast in 4 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in long context, where Grok 4 Fast leads 63.2 to 41.0.
- The biggest single-benchmark swing is ARC-AGI-1: 16.5% for Grok-3 mini and 48.5% for Grok 4 Fast.

## Snapshot

| | Grok-3 mini | Grok 4 Fast |
|---|---|---|
| Provider | xAI | xAI |
| Noometry Index | 41.0 | 39.0 |
| Rank | 130 | 164 |
| Context | — | — |
| Input $/M | — | — |
| Output $/M | — | — |
| Weights | Proprietary | Proprietary |

## Coding

- Grok-3 mini: 40.4 (#126)
- Grok 4 Fast: 32.3 (#264)

| Benchmark | Grok-3 mini | Grok 4 Fast |
|---|---|---|
| WeirdML | 42.6% | 42.9% |
| LMArena Coding | 1380 | 1429 |
| Aider Polyglot | 49.3% | — |
| LMArena WebDev | — | 1160 |

## Agentic & Tool Use

- Grok-3 mini: —
- Grok 4 Fast: 29.3 (#80)

| Benchmark | Grok-3 mini | Grok 4 Fast |
|---|---|---|
| τ²-bench Banking | — | 15.7% |
| Cybench | — | 30% |
| LMArena Search | — | 1171 |

## Reasoning

- Grok-3 mini: 13.8 (#323)
- Grok 4 Fast: 22.5 (#179)

| Benchmark | Grok-3 mini | Grok 4 Fast |
|---|---|---|
| ARC-AGI-2 | 0.4% | 5.3% |
| Kagi LLM Benchmark | 61.3% | 66.1% |
| ARC-AGI-1 | 16.5% | 48.5% |
| LMArena Hard Prompts | 1374 | 1413 |
| Epoch Capabilities Index | 140.35 | 144.21 |
| DTBench | — | 82.7% |
| ForecastBench | — | 60.5 |

## Math

- Grok-3 mini: 40.3 (#78)
- Grok 4 Fast: 36.1 (#126)

| Benchmark | Grok-3 mini | Grok 4 Fast |
|---|---|---|
| LMArena Math | 1386 | 1419 |
| OTIS Mock AIME 2024-2025 | 77.8% | — |
| Omni-MATH | 31.8% | — |
| MATH Level 5 | 90.9% | — |
| FrontierMath (Feb 2025 set) | 5.9% | — |

## Knowledge

- Grok-3 mini: 46.3 (#75)
- Grok 4 Fast: 31.5 (#211)

| Benchmark | Grok-3 mini | Grok 4 Fast |
|---|---|---|
| LMArena Expert | 1395 | 1411 |
| GPQA Diamond | 76.3% | — |
| MMLU-Pro | 79.9% | — |
| Confabulations | 10.8% | — |
| Vectara Hallucination Rate | — | 19.7% |
| GPQA (HELM) | 67.5% | — |

## Multilingual

- Grok-3 mini: 48.3 (#141)
- Grok 4 Fast: 51.5 (#106)

| Benchmark | Grok-3 mini | Grok 4 Fast |
|---|---|---|
| LMArena Non-English | 1352 | 1397 |
| LMArena Chinese | 1387 | 1458 |
| LMArena French | 1357 | 1433 |
| LMArena German | 1350 | 1383 |
| LMArena Japanese | 1343 | 1358 |
| LMArena Korean | 1336 | 1359 |
| LMArena Russian | 1352 | 1387 |
| LMArena Spanish | 1379 | 1414 |

## Instruction Following

- Grok-3 mini: 78.7 (#8)
- Grok 4 Fast: 73.4 (#116)

| Benchmark | Grok-3 mini | Grok 4 Fast |
|---|---|---|
| LMArena Instruction Following | 1356 | 1388 |
| IFEval | 95.1% | — |

## Long Context

- Grok-3 mini: 41.0 (#142)
- Grok 4 Fast: 63.2 (#3)

| Benchmark | Grok-3 mini | Grok 4 Fast |
|---|---|---|
| Fiction.LiveBench | 66.7% | 94.4% |
| LMArena Longer Query | 1372 | 1415 |

## Writing & Preference

- Grok-3 mini: 52.7 (#163)
- Grok 4 Fast: 60.2 (#96)

| Benchmark | Grok-3 mini | Grok 4 Fast |
|---|---|---|
| LMArena Text | 1370 | 1407 |
| LMArena Creative Writing | 1342 | 1388 |
| LMArena Multi-Turn | 1355 | 1414 |
| Short-Story Creative Writing | 73.5% | — |
| WildBench | 65.1% | — |

## FAQ

### Is Grok-3 mini better than Grok 4 Fast?

Grok-3 mini is the stronger model overall, scoring 41.0 to 39.0 on the Noometry Index.

### Is Grok-3 mini or Grok 4 Fast better for coding?

Grok-3 mini scores higher on coding benchmarks: 40.4 versus 32.3 in the Noometry coding category.

### How many benchmarks do Grok-3 mini and Grok 4 Fast share?

23 benchmarks have published results for both models. Grok-3 mini has 35 scored results on Noometry and Grok 4 Fast has 30.