# Gemini 3.8 Flash vs Grok 4.20 Multi-Agent

> Gemini 3.8 Flash is the stronger model overall, scoring 59.5 to 45.5 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gemini-3-8-flash-vs-grok-4-20-multi-agent
- Last updated: 2026-10-10
- Shared benchmarks: 19

## Summary

- They share 19 benchmarks with published results for both. Gemini 3.8 Flash scores higher in 9 categories and Grok 4.20 Multi-Agent in 0 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in knowledge, where Gemini 3.8 Flash leads 74.9 to 39.7.
- The biggest single-benchmark swing is NYT Connections (extended): 97.4% for Gemini 3.8 Flash and 89.6% for Grok 4.20 Multi-Agent.
- Both cost about the same: $0.75 input and $3.75 output per million tokens.
- Gemini 3.8 Flash accepts more context: 1.05M tokens versus 1M.

## Snapshot

| | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| Provider | Google | xAI |
| Noometry Index | 59.5 | 45.5 |
| Rank | 13 | 62 |
| Context | 1.05M | 1M |
| Input $/M | $0.75 | $1.25 |
| Output $/M | $3.75 | $2.50 |
| Weights | Proprietary | Proprietary |

## Coding

- Gemini 3.8 Flash: 56.4 (#17)
- Grok 4.20 Multi-Agent: 42.4 (#91)

| Benchmark | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Coding | 1512 | 1458 |
| DeepSWE | 73.8% | — |
| FrontierCode | 41.2% | — |
| CursorBench | 39.6% | — |
| LMArena WebDev | 1581 | — |
| FrontierSWE | 19.6% | — |
| SciCode | 56.6% | — |
| ALE-Bench | 1,270 | — |

## Agentic & Tool Use

- Gemini 3.8 Flash: 40.3 (#22)
- Grok 4.20 Multi-Agent: —

| Benchmark | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| APEX-Agents | 64.3% | — |
| GDP.pdf | 23.4% | — |
| LMArena Search | — | 1204 |
| Vending-Bench 2 | 5,094 | — |

## Reasoning

- Gemini 3.8 Flash: 64.7 (#13)
- Grok 4.20 Multi-Agent: 42.4 (#44)

| Benchmark | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| NYT Connections (extended) | 97.4% | 89.6% |
| LMArena Hard Prompts | 1506 | 1448 |
| CritPt | 18.3% | — |
| Chess Puzzles | 61% | — |
| Mystery Game Puzzles | 47% | — |
| DTBench | 95.7% | — |
| LMCA | 52.9% | — |
| Surface Evolver Bench | 76.9% | — |
| Epoch Capabilities Index | 157.13 | — |

## Math

- Gemini 3.8 Flash: 65.2 (#22)
- Grok 4.20 Multi-Agent: 36.6 (#106)

| Benchmark | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Math | 1528 | 1441 |
| FrontierMath (Tiers 1-3) | 68.4% | — |
| FrontierMath Tier 4 | 22% | — |
| OTIS Mock AIME 2024-2025 | 98.9% | — |
| ProofBench | 48% | — |

## Knowledge

- Gemini 3.8 Flash: 74.9 (#2)
- Grok 4.20 Multi-Agent: 39.7 (#116)

| Benchmark | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Expert | 1529 | 1445 |
| GPQA Diamond | 95.4% | — |
| Humanity's Last Exam | 44.5% | — |
| SimpleQA Verified | 69.7% | — |

## Multimodal

- Gemini 3.8 Flash: 40.9 (#33)
- Grok 4.20 Multi-Agent: 39.8 (#44)

| Benchmark | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Vision | 1312 | 1259 |
| Blueprint-Bench 2 | 38.6% | — |
| Furniture Assembly | 31.7% | — |

## Multilingual

- Gemini 3.8 Flash: 57.9 (#5)
- Grok 4.20 Multi-Agent: 54.6 (#40)

| Benchmark | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Non-English | 1486 | 1440 |
| LMArena Chinese | 1547 | 1475 |
| LMArena French | 1502 | 1467 |
| LMArena German | 1470 | 1456 |
| LMArena Japanese | 1505 | 1405 |
| LMArena Korean | 1479 | 1416 |
| LMArena Russian | 1507 | 1457 |
| LMArena Spanish | 1492 | 1447 |

## Instruction Following

- Gemini 3.8 Flash: 78.2 (#11)
- Grok 4.20 Multi-Agent: 75.0 (#80)

| Benchmark | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Instruction Following | 1489 | 1420 |

## Long Context

- Gemini 3.8 Flash: 46.2 (#23)
- Grok 4.20 Multi-Agent: 43.7 (#84)

| Benchmark | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Longer Query | 1506 | 1430 |

## Writing & Preference

- Gemini 3.8 Flash: 72.1 (#16)
- Grok 4.20 Multi-Agent: 64.1 (#57)

| Benchmark | Gemini 3.8 Flash | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Text | 1494 | 1450 |
| LMArena Creative Writing | 1485 | 1435 |
| LMArena Multi-Turn | 1503 | 1451 |
| EQ-Bench Creative Writing | 1748 | — |

## FAQ

### Is Gemini 3.8 Flash better than Grok 4.20 Multi-Agent?

Gemini 3.8 Flash is the stronger model overall, scoring 59.5 to 45.5 on the Noometry Index.

### Which is cheaper, Gemini 3.8 Flash or Grok 4.20 Multi-Agent?

Gemini 3.8 Flash is cheaper. It lists at $0.75 per million input tokens and $3.75 per million output tokens; Grok 4.20 Multi-Agent lists at $1.25 and $2.50.

### Is Gemini 3.8 Flash or Grok 4.20 Multi-Agent better for coding?

Gemini 3.8 Flash scores higher on coding benchmarks: 56.4 versus 42.4 in the Noometry coding category.

### Which has the bigger context window?

Gemini 3.8 Flash does, with 1.05M tokens against 1M.

### How many benchmarks do Gemini 3.8 Flash and Grok 4.20 Multi-Agent share?

19 benchmarks have published results for both models. Gemini 3.8 Flash has 46 scored results on Noometry and Grok 4.20 Multi-Agent has 20.