# Gemini 3.1 Flash Lite vs Grok 4 Fast

> Gemini 3.1 Flash Lite is the stronger model overall, scoring 40.4 to 39.0 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gemini-3-1-flash-lite-vs-grok-4-fast
- Last updated: 2026-10-10
- Shared benchmarks: 24

## Summary

- They share 24 benchmarks with published results for both. Gemini 3.1 Flash Lite scores higher in 6 categories and Grok 4 Fast in 3 categories; 4 gaps are clear of the uncertainty.
- The widest gap is in long context, where Grok 4 Fast leads 63.2 to 42.5.
- The biggest single-benchmark swing is Vectara Hallucination Rate: 8.2% for Gemini 3.1 Flash Lite and 19.7% for Grok 4 Fast.

## Snapshot

| | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| Provider | Google | xAI |
| Noometry Index | 40.4 | 39.0 |
| Rank | 141 | 164 |
| Context | 1.05M | — |
| Input $/M | $0.25 | — |
| Output $/M | $1.50 | — |
| Weights | Proprietary | Proprietary |

## Coding

- Gemini 3.1 Flash Lite: 37.5 (#179)
- Grok 4 Fast: 32.3 (#264)

| Benchmark | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| LMArena WebDev | 1256 | 1160 |
| WeirdML | 52.2% | 42.9% |
| LMArena Coding | 1400 | 1429 |
| SciCode | 41.9% | — |
| ALE-Bench | 797.73 | — |

## Agentic & Tool Use

- Gemini 3.1 Flash Lite: 29.9 (#72)
- Grok 4 Fast: 29.3 (#80)

| Benchmark | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| τ²-bench Banking | — | 15.7% |
| Cybench | — | 30% |
| DeepResearch Bench | 37.3% | — |
| LMArena Search | — | 1171 |

## Reasoning

- Gemini 3.1 Flash Lite: 22.3 (#181)
- Grok 4 Fast: 22.5 (#179)

| Benchmark | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| Kagi LLM Benchmark | 67.2% | 66.1% |
| LMArena Hard Prompts | 1407 | 1413 |
| DTBench | 76.8% | 82.7% |
| Epoch Capabilities Index | 144.45 | 144.21 |
| ForecastBench | 54.4 | 60.5 |
| ARC-AGI-2 | — | 5.3% |
| NYT Connections (extended) | 8.2% | — |
| ARC-AGI-1 | — | 48.5% |
| CritPt | 1.1% | — |
| Chess Puzzles | 25% | — |
| EnigmaEval | 3% | — |
| Thematic Generalization | 63.3% | — |
| LMCA | 35% | — |

## Math

- Gemini 3.1 Flash Lite: 39.5 (#82)
- Grok 4 Fast: 36.1 (#126)

| Benchmark | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| LMArena Math | 1427 | 1419 |
| FrontierMath (Tiers 1-3) | 27.7% | — |
| OTIS Mock AIME 2024-2025 | 80% | — |

## Knowledge

- Gemini 3.1 Flash Lite: 41.7 (#95)
- Grok 4 Fast: 31.5 (#211)

| Benchmark | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| Vectara Hallucination Rate | 8.2% | 19.7% |
| LMArena Expert | 1397 | 1411 |
| GPQA Diamond | 81.8% | — |
| Humanity's Last Exam | 8.6% | — |

## Multimodal

- Gemini 3.1 Flash Lite: 38.7 (#57)
- Grok 4 Fast: —

| Benchmark | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| LMArena Vision | 1240 | — |

## Multilingual

- Gemini 3.1 Flash Lite: 52.5 (#82)
- Grok 4 Fast: 51.5 (#106)

| Benchmark | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| LMArena Non-English | 1410 | 1397 |
| LMArena Chinese | 1461 | 1458 |
| LMArena French | 1423 | 1433 |
| LMArena German | 1429 | 1383 |
| LMArena Japanese | 1411 | 1358 |
| LMArena Korean | 1393 | 1359 |
| LMArena Russian | 1420 | 1387 |
| LMArena Spanish | 1420 | 1414 |

## Instruction Following

- Gemini 3.1 Flash Lite: 72.9 (#126)
- Grok 4 Fast: 73.4 (#116)

| Benchmark | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| LMArena Instruction Following | 1376 | 1388 |

## Long Context

- Gemini 3.1 Flash Lite: 42.5 (#117)
- Grok 4 Fast: 63.2 (#3)

| Benchmark | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| LMArena Longer Query | 1394 | 1415 |
| Fiction.LiveBench | — | 94.4% |

## Writing & Preference

- Gemini 3.1 Flash Lite: 61.0 (#90)
- Grok 4 Fast: 60.2 (#96)

| Benchmark | Gemini 3.1 Flash Lite | Grok 4 Fast |
|---|---|---|
| LMArena Text | 1416 | 1407 |
| LMArena Creative Writing | 1401 | 1388 |
| LMArena Multi-Turn | 1417 | 1414 |

## FAQ

### Is Gemini 3.1 Flash Lite better than Grok 4 Fast?

Gemini 3.1 Flash Lite is the stronger model overall, scoring 40.4 to 39.0 on the Noometry Index.

### Is Gemini 3.1 Flash Lite or Grok 4 Fast better for coding?

Gemini 3.1 Flash Lite scores higher on coding benchmarks: 37.5 versus 32.3 in the Noometry coding category.

### How many benchmarks do Gemini 3.1 Flash Lite and Grok 4 Fast share?

24 benchmarks have published results for both models. Gemini 3.1 Flash Lite has 38 scored results on Noometry and Grok 4 Fast has 30.