# Gemini 3.1 Pro Preview vs Gemini 3 Flash Preview

> Gemini 3.1 Pro Preview is the stronger model overall, scoring 56.7 to 52.3 on the Noometry Index. Gemini 3 Flash Preview costs 4.0× less per token, which makes it the better buy when Gemini 3.1 Pro Preview's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gemini-3-1-pro-preview-vs-gemini-3-flash-preview
- Last updated: 2026-10-10
- Shared benchmarks: 52

## Summary

- They share 52 benchmarks with published results for both. Gemini 3.1 Pro Preview scores higher in 7 categories and Gemini 3 Flash Preview in 3 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Gemini 3.1 Pro Preview leads 71.7 to 49.2.
- The biggest single-benchmark swing is ARC-AGI-2: 77.1% for Gemini 3.1 Pro Preview and 33.6% for Gemini 3 Flash Preview.
- Gemini 3 Flash Preview is cheaper at $0.50 / $3 per million input/output tokens, against $2 / $12 for Gemini 3.1 Pro Preview.

## Snapshot

| | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| Provider | Google | Google |
| Noometry Index | 56.7 | 52.3 |
| Rank | 23 | 40 |
| Context | 1.05M | 1.05M |
| Input $/M | $2 | $0.50 |
| Output $/M | $12 | $3 |
| Weights | Proprietary | Proprietary |

## Coding

- Gemini 3.1 Pro Preview: 42.5 (#99)
- Gemini 3 Flash Preview: 50.9 (#42)

| Benchmark | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| SWE-bench Verified | 75.6% | 75.4% |
| LMArena WebDev | 1447 | 1439 |
| GSO | 22.6% | 9.8% |
| WeirdML | 72.1% | 61.6% |
| LMArena Coding | 1484 | 1460 |
| ALE-Bench | 1,161 | 1,367 |
| DeepSWE | 11.7% | — |
| SWE-bench Verified (bash only) | — | 75.8% |
| SWE-bench Multilingual | — | 72.7% |
| SciCode | 58.9% | — |
| MirrorCode | 8.9% | — |
| AlgoTune | 2.02 | — |

## Agentic & Tool Use

- Gemini 3.1 Pro Preview: 37.7 (#34)
- Gemini 3 Flash Preview: 38.7 (#29)

| Benchmark | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| Terminal-Bench | 80.2% | 64.3% |
| τ²-bench Banking | 26% | 27.3% |
| DeepResearch Bench | 47.8% | 49.8% |
| BALROG | 57% | 48.1% |
| GDP.pdf | 17% | 10% |
| LMArena Search | 1211 | 1198 |
| Vending-Bench 2 | 3,774 | 3,635 |
| APEX-Agents | 35.3% | — |
| τ²-bench Airline | — | 82.5% |
| τ²-bench Retail | — | 76.8% |
| τ²-bench Telecom | — | 91.2% |
| PostTrainBench | 22% | — |
| ExploitBench | 26.1% | — |
| GBAEval | 0.8% | — |
| METR Time Horizons | 77% | — |

## Reasoning

- Gemini 3.1 Pro Preview: 71.7 (#12)
- Gemini 3 Flash Preview: 49.2 (#37)

| Benchmark | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| ARC-AGI-2 | 77.1% | 33.6% |
| SimpleBench | 79.6% | 61.1% |
| NYT Connections (extended) | 97.4% | 83.1% |
| ARC-AGI-1 | 98% | 84.7% |
| Chess Puzzles | 55% | 40% |
| LMArena Hard Prompts | 1485 | 1465 |
| Mystery Game Puzzles | 34% | 26% |
| DTBench | 97.1% | 89.1% |
| LMCA | 53.8% | 43.1% |
| Epoch Capabilities Index | 154.77 | 151.8 |
| ForecastBench | 59 | 58.5 |
| CritPt | 17.7% | — |
| EnigmaEval | 36.8% | — |
| Thematic Generalization | 79.4% | — |
| EBR-Bench | 14.3% | — |

## Math

- Gemini 3.1 Pro Preview: 62.1 (#34)
- Gemini 3 Flash Preview: 51.7 (#55)

| Benchmark | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| FrontierMath (Tiers 1-3) | 59.6% | 51.2% |
| FrontierMath Tier 4 | 26.8% | 17.1% |
| MathArena Final-Answer Competitions | 86.5% | 67.6% |
| OTIS Mock AIME 2024-2025 | 95.6% | 95.6% |
| ProofBench | 26% | 15% |
| LMArena Math | 1485 | 1473 |
| FrontierMath (Feb 2025 set) | 36.9% | 35.6% |
| FrontierMath Tier 4 (v1) | 16.7% | 4.2% |

## Knowledge

- Gemini 3.1 Pro Preview: 71.8 (#3)
- Gemini 3 Flash Preview: 58.8 (#33)

| Benchmark | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| GPQA Diamond | 94.4% | 89.4% |
| SimpleQA Verified | 73.5% | 66.8% |
| Vectara Hallucination Rate | 10.4% | 13.5% |
| LMArena Expert | 1485 | 1462 |
| Humanity's Last Exam | 46.4% | — |

## Multimodal

- Gemini 3.1 Pro Preview: 37.9 (#69)
- Gemini 3 Flash Preview: 45.5 (#16)

| Benchmark | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| LMArena Vision | 1296 | 1285 |
| Blueprint-Bench 2 | 26.5% | 0% |
| LMArena Document | 1444 | 1413 |
| GeoBench | — | 88% |
| VPCT | — | 72.6% |
| Furniture Assembly | 26.7% | — |

## Multilingual

- Gemini 3.1 Pro Preview: 57.0 (#12)
- Gemini 3 Flash Preview: 55.7 (#27)

| Benchmark | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| LMArena Non-English | 1477 | 1458 |
| LMArena Chinese | 1529 | 1511 |
| LMArena French | 1487 | 1477 |
| LMArena German | 1491 | 1497 |
| LMArena Japanese | 1493 | 1489 |
| LMArena Korean | 1455 | 1443 |
| LMArena Russian | 1498 | 1480 |
| LMArena Spanish | 1479 | 1469 |

## Instruction Following

- Gemini 3.1 Pro Preview: 77.0 (#32)
- Gemini 3 Flash Preview: 75.7 (#56)

| Benchmark | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| LMArena Instruction Following | 1466 | 1437 |

## Long Context

- Gemini 3.1 Pro Preview: 47.4 (#18)
- Gemini 3 Flash Preview: 44.4 (#67)

| Benchmark | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| LMArena Longer Query | 1483 | 1452 |
| CL-bench | 20.8% | — |
| CL-bench Life | 16.9% | — |

## Writing & Preference

- Gemini 3.1 Pro Preview: 66.1 (#37)
- Gemini 3 Flash Preview: 65.5 (#45)

| Benchmark | Gemini 3.1 Pro Preview | Gemini 3 Flash Preview |
|---|---|---|
| LMArena Text | 1481 | 1466 |
| LMArena Creative Writing | 1482 | 1457 |
| LMArena Multi-Turn | 1488 | 1471 |
| EQ-Bench Creative Writing | 1491 | — |
| EQ-Bench 4 | 1142 | — |

## FAQ

### Is Gemini 3.1 Pro Preview better than Gemini 3 Flash Preview?

Gemini 3.1 Pro Preview is the stronger model overall, scoring 56.7 to 52.3 on the Noometry Index. Gemini 3 Flash Preview costs 4.0× less per token, which makes it the better buy when Gemini 3.1 Pro Preview's lead doesn't matter for your workload.

### Which is cheaper, Gemini 3.1 Pro Preview or Gemini 3 Flash Preview?

Gemini 3 Flash Preview is cheaper. It lists at $0.50 per million input tokens and $3 per million output tokens; Gemini 3.1 Pro Preview lists at $2 and $12.

### Is Gemini 3.1 Pro Preview or Gemini 3 Flash Preview better for coding?

Gemini 3 Flash Preview scores higher on coding benchmarks: 50.9 versus 42.5 in the Noometry coding category.

### Which has the bigger context window?

Both accept 1.05M tokens.

### How many benchmarks do Gemini 3.1 Pro Preview and Gemini 3 Flash Preview share?

52 benchmarks have published results for both models. Gemini 3.1 Pro Preview has 71 scored results on Noometry and Gemini 3 Flash Preview has 59.