# Gemini 3.5 Flash vs Mercury 2

> Gemini 3.5 Flash is the stronger model overall, scoring 54.1 to 38.8 on the Noometry Index. Mercury 2 costs 9.0× less per token, which makes it the better buy when Gemini 3.5 Flash's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gemini-3-5-flash-vs-mercury-2
- Last updated: 2026-10-10
- Shared benchmarks: 16

## Summary

- They share 16 benchmarks with published results for both. Gemini 3.5 Flash scores higher in 7 categories and Mercury 2 in 0 categories; 7 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Gemini 3.5 Flash leads 62.7 to 23.0.
- The biggest single-benchmark swing is WeirdML: 62.6% for Gemini 3.5 Flash and 43.2% for Mercury 2.
- Mercury 2 is cheaper at $0.25 / $0.75 per million input/output tokens, against $1.50 / $9 for Gemini 3.5 Flash.
- Gemini 3.5 Flash accepts more context: 1.05M tokens versus 128K.

## Snapshot

| | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| Provider | Google | Inception |
| Noometry Index | 54.1 | 38.8 |
| Rank | 29 | 167 |
| Context | 1.05M | 128K |
| Input $/M | $1.50 | $0.25 |
| Output $/M | $9 | $0.75 |
| Weights | Proprietary | Proprietary |

## Coding

- Gemini 3.5 Flash: 49.1 (#46)
- Mercury 2: 33.2 (#250)

| Benchmark | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| LMArena WebDev | 1499 | 1170 |
| SciCode | 53.1% | 38.7% |
| WeirdML | 62.6% | 43.2% |
| LMArena Coding | 1492 | 1391 |
| ALE-Bench | 911.02 | 785.58 |
| SWE-bench Verified | 79.3% | — |
| DeepSWE | 37.4% | — |

## Agentic & Tool Use

- Gemini 3.5 Flash: 24.8 (#107)
- Mercury 2: —

| Benchmark | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| APEX-Agents | 27.5% | — |
| GBAEval | 6.7% | — |
| GDP.pdf | 14% | — |
| Vending-Bench 2 | 5,396 | — |

## Reasoning

- Gemini 3.5 Flash: 62.7 (#16)
- Mercury 2: 23.0 (#170)

| Benchmark | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| CritPt | 13.1% | 0.8% |
| LMArena Hard Prompts | 1488 | 1362 |
| ARC-AGI-2 | 72.1% | — |
| SimpleBench | 76.7% | — |
| NYT Connections (extended) | 92.6% | — |
| ARC-AGI-1 | 92.5% | — |
| Chess Puzzles | 50% | — |
| EnigmaEval | 25.4% | — |
| EBR-Bench | 4.8% | — |
| Mystery Game Puzzles | 32% | — |
| DTBench | 94.7% | — |
| LMCA | 47.1% | — |
| Surface Evolver Bench | 58.1% | — |
| Epoch Capabilities Index | 154.55 | — |
| ForecastBench | 59 | — |

## Math

- Gemini 3.5 Flash: 60.5 (#30)
- Mercury 2: —

| Benchmark | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| FrontierMath (Tiers 1-3) | 62.8% | — |
| FrontierMath Tier 4 | 26.8% | — |
| MathArena Final-Answer Competitions | 76.3% | — |
| OTIS Mock AIME 2024-2025 | 95.6% | — |
| ProofBench | 31% | — |
| LMArena Math | 1502 | — |
| FrontierMath (Feb 2025 set) | 39% | — |
| FrontierMath Tier 4 (v1) | 14.6% | — |

## Knowledge

- Gemini 3.5 Flash: 66.3 (#10)
- Mercury 2: 35.6 (#170)

| Benchmark | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| LMArena Expert | 1493 | 1358 |
| GPQA Diamond | 92.8% | — |
| SimpleQA Verified | 66.2% | — |
| Vectara Hallucination Rate | — | 12.3% |

## Multimodal

- Gemini 3.5 Flash: 45.7 (#13)
- Mercury 2: —

| Benchmark | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| LMArena Vision | 1311 | — |
| Blueprint-Bench 2 | 33.6% | — |
| LMArena Document | 1463 | — |

## Multilingual

- Gemini 3.5 Flash: 57.1 (#12)
- Mercury 2: 46.8 (#153)

| Benchmark | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| LMArena Non-English | 1475 | 1331 |
| LMArena Chinese | 1525 | 1416 |
| LMArena Russian | 1491 | 1303 |
| LMArena French | 1490 | — |
| LMArena German | 1500 | — |
| LMArena Japanese | 1481 | — |
| LMArena Korean | 1453 | — |
| LMArena Spanish | 1478 | — |

## Instruction Following

- Gemini 3.5 Flash: 77.2 (#29)
- Mercury 2: 70.4 (#161)

| Benchmark | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| LMArena Instruction Following | 1466 | 1328 |

## Long Context

- Gemini 3.5 Flash: 45.3 (#39)
- Mercury 2: 40.4 (#149)

| Benchmark | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| LMArena Longer Query | 1481 | 1329 |

## Writing & Preference

- Gemini 3.5 Flash: 65.5 (#46)
- Mercury 2: 54.0 (#151)

| Benchmark | Gemini 3.5 Flash | Mercury 2 |
|---|---|---|
| LMArena Text | 1481 | 1355 |
| LMArena Creative Writing | 1467 | 1289 |
| LMArena Multi-Turn | 1482 | 1358 |
| EQ-Bench 4 | 1087 | — |

## FAQ

### Is Gemini 3.5 Flash better than Mercury 2?

Gemini 3.5 Flash is the stronger model overall, scoring 54.1 to 38.8 on the Noometry Index. Mercury 2 costs 9.0× less per token, which makes it the better buy when Gemini 3.5 Flash's lead doesn't matter for your workload.

### Which is cheaper, Gemini 3.5 Flash or Mercury 2?

Mercury 2 is cheaper. It lists at $0.25 per million input tokens and $0.75 per million output tokens; Gemini 3.5 Flash lists at $1.50 and $9.

### Is Gemini 3.5 Flash or Mercury 2 better for coding?

Gemini 3.5 Flash scores higher on coding benchmarks: 49.1 versus 33.2 in the Noometry coding category.

### Which has the bigger context window?

Gemini 3.5 Flash does, with 1.05M tokens against 128K.

### How many benchmarks do Gemini 3.5 Flash and Mercury 2 share?

16 benchmarks have published results for both models. Gemini 3.5 Flash has 54 scored results on Noometry and Mercury 2 has 17.