# Gemini 1.5 Flash 8B vs Grok 4.1 Fast

> Grok 4.1 Fast is the stronger model overall, scoring 41.4 to 29.9 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gemini-1-5-flash-8b-vs-grok-4-1-fast
- Last updated: 2026-10-10
- Shared benchmarks: 19

## Summary

- They share 19 benchmarks with published results for both. Gemini 1.5 Flash 8B scores higher in 1 category and Grok 4.1 Fast in 8 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Grok 4.1 Fast leads 43.4 to 20.0.
- The biggest single-benchmark swing is DTBench: 50% for Gemini 1.5 Flash 8B and 87.7% for Grok 4.1 Fast.

## Snapshot

| | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| Provider | Google | xAI |
| Noometry Index | 29.9 | 41.4 |
| Rank | 301 | 136 |
| Context | — | 128K |
| Input $/M | — | $0.20 |
| Output $/M | — | $0.50 |
| Weights | Proprietary | Proprietary |

## Coding

- Gemini 1.5 Flash 8B: 35.5 (#225)
- Grok 4.1 Fast: 34.1 (#245)

| Benchmark | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Coding | 1218 | 1411 |
| LMArena WebDev | — | 1242 |
| ALE-Bench | — | 394.93 |

## Agentic & Tool Use

- Gemini 1.5 Flash 8B: —
- Grok 4.1 Fast: 36.3 (#39)

| Benchmark | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| Berkeley Function Calling Leaderboard | — | 69.6% |
| τ²-bench Banking | — | 13.1% |
| LMArena Search | — | 1171 |
| Vending-Bench 2 | — | 1,107 |

## Reasoning

- Gemini 1.5 Flash 8B: 20.0 (#244)
- Grok 4.1 Fast: 43.4 (#49)

| Benchmark | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Hard Prompts | 1209 | 1407 |
| DTBench | 50% | 87.7% |
| SimpleBench | — | 56% |
| NYT Connections (extended) | — | 87.4% |
| ForecastBench | — | 61 |

## Math

- Gemini 1.5 Flash 8B: 14.2 (#302)
- Grok 4.1 Fast: 31.9 (#221)

| Benchmark | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Math | 1207 | 1408 |
| MathArena Final-Answer Competitions | — | 60.9% |
| OTIS Mock AIME 2024-2025 | 4.6% | — |
| ProofBench | — | 4% |

## Knowledge

- Gemini 1.5 Flash 8B: 16.0 (#289)
- Grok 4.1 Fast: 33.1 (#207)

| Benchmark | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Expert | 1185 | 1399 |
| GPQA Diamond | 33% | — |
| Vectara Hallucination Rate | — | 17.8% |

## Multimodal

- Gemini 1.5 Flash 8B: 28.2 (#115)
- Grok 4.1 Fast: 37.0 (#76)

| Benchmark | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Vision | 1044 | 1201 |

## Multilingual

- Gemini 1.5 Flash 8B: 38.5 (#229)
- Grok 4.1 Fast: 51.0 (#114)

| Benchmark | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Non-English | 1215 | 1391 |
| LMArena Chinese | 1231 | 1441 |
| LMArena French | 1234 | 1415 |
| LMArena German | 1206 | 1404 |
| LMArena Japanese | 1150 | 1349 |
| LMArena Korean | 1140 | 1361 |
| LMArena Russian | 1236 | 1387 |
| LMArena Spanish | 1212 | 1413 |

## Instruction Following

- Gemini 1.5 Flash 8B: 62.8 (#236)
- Grok 4.1 Fast: 72.7 (#133)

| Benchmark | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Instruction Following | 1199 | 1376 |

## Long Context

- Gemini 1.5 Flash 8B: 37.0 (#225)
- Grok 4.1 Fast: 42.4 (#126)

| Benchmark | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Longer Query | 1219 | 1390 |

## Writing & Preference

- Gemini 1.5 Flash 8B: 42.8 (#232)
- Grok 4.1 Fast: 57.2 (#131)

| Benchmark | Gemini 1.5 Flash 8B | Grok 4.1 Fast |
|---|---|---|
| LMArena Text | 1226 | 1408 |
| LMArena Creative Writing | 1218 | 1394 |
| LMArena Multi-Turn | 1185 | 1389 |
| EQ-Bench Creative Writing | — | 1327 |

## FAQ

### Is Gemini 1.5 Flash 8B better than Grok 4.1 Fast?

Grok 4.1 Fast is the stronger model overall, scoring 41.4 to 29.9 on the Noometry Index.

### Is Gemini 1.5 Flash 8B or Grok 4.1 Fast better for coding?

Gemini 1.5 Flash 8B scores higher on coding benchmarks: 35.5 versus 34.1 in the Noometry coding category.

### How many benchmarks do Gemini 1.5 Flash 8B and Grok 4.1 Fast share?

19 benchmarks have published results for both models. Gemini 1.5 Flash 8B has 21 scored results on Noometry and Grok 4.1 Fast has 32.