# Gemini 2.5 Pro vs Step 3.5 Flash

> Gemini 2.5 Pro is the stronger model overall, scoring 45.0 to 42.3 on the Noometry Index. Step 3.5 Flash costs 23× less per token, which makes it the better buy when Gemini 2.5 Pro's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gemini-2-5-pro-vs-step-3-5-flash
- Last updated: 2026-10-11
- Shared benchmarks: 17

## Summary

- They share 17 benchmarks with published results for both. Gemini 2.5 Pro scores higher in 7 categories and Step 3.5 Flash in 1 category; 7 gaps are clear of the uncertainty.
- The widest gap is in long context, where Gemini 2.5 Pro leads 59.8 to 42.8.
- Step 3.5 Flash is cheaper at $0.10 / $0.30 per million input/output tokens, against $1.25 / $10 for Gemini 2.5 Pro.
- Gemini 2.5 Pro accepts more context: 1.05M tokens versus 256K.
- Step 3.5 Flash has downloadable open weights; the other is API-only.

## Snapshot

| | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| Provider | Google | StepFun |
| Noometry Index | 45.0 | 42.3 |
| Rank | 75 | 116 |
| Context | 1.05M | 256K |
| Input $/M | $1.25 | $0.10 |
| Output $/M | $10 | $0.30 |
| Weights | Proprietary | Open |

## Coding

- Gemini 2.5 Pro: 42.4 (#101)
- Step 3.5 Flash: 42.4 (#105)

| Benchmark | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| LMArena Coding | 1452 | 1436 |
| SWE-bench Verified | 57.6% | — |
| SWE-bench Verified (bash only) | 53.6% | — |
| Aider Polyglot | 83.1% | — |
| LMArena WebDev | 1227 | — |
| SciCode | 42.8% | — |
| GSO | 3.9% | — |
| WeirdML | 54% | — |
| LiveBench Coding | 85.9% | — |
| CadEval | 64% | — |
| ALE-Bench | 785.52 | — |
| AlgoTune | 1.51 | — |

## Agentic & Tool Use

- Gemini 2.5 Pro: 29.2 (#88)
- Step 3.5 Flash: —

| Benchmark | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| Terminal-Bench | 32.6% | — |
| GDPval | 23.3% | — |
| Remote Labor Index | 0.8% | — |
| TheAgentCompany | 30.3% | — |
| τ²-bench Banking | 13.7% | — |
| DeepResearch Bench | 42.8% | — |
| BALROG | 43.3% | — |
| LMArena Search | 1142 | — |
| METR Time Horizons | 55.4% | — |
| Vending-Bench 2 | 573.64 | — |

## Reasoning

- Gemini 2.5 Pro: 28.8 (#99)
- Step 3.5 Flash: 22.2 (#202)

| Benchmark | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| LMArena Hard Prompts | 1455 | 1411 |
| ARC-AGI-2 | 4.9% | — |
| SimpleBench | 62.4% | — |
| Kagi LLM Benchmark | 70.3% | — |
| NYT Connections (extended) | — | 28.4% |
| ARC-AGI-1 | 41% | — |
| CritPt | 2% | — |
| Chess Puzzles | 20% | — |
| EnigmaEval | 5.6% | — |
| LiveBench Reasoning | 89.8% | — |
| DTBench | 82.4% | — |
| LiveBench Data Analysis | 79.9% | — |
| LMCA | 34.8% | — |
| Epoch Capabilities Index | 145.32 | — |
| ForecastBench | 61.3 | — |
| LiveBench | 82.3% | — |

## Math

- Gemini 2.5 Pro: 32.5 (#213)
- Step 3.5 Flash: 42.6 (#84)

| Benchmark | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| LMArena Math | 1450 | 1408 |
| FrontierMath (Tiers 1-3) | 24.6% | — |
| FrontierMath Tier 4 | 0% | — |
| MathArena Final-Answer Competitions | — | 66.8% |
| OTIS Mock AIME 2024-2025 | 84.7% | — |
| Omni-MATH | 41.6% | — |
| LiveBench Math | 90.2% | — |
| MATH Level 5 | 95.9% | — |
| FrontierMath (Feb 2025 set) | 14.1% | — |
| FrontierMath Tier 4 (v1) | 4.2% | — |

## Knowledge

- Gemini 2.5 Pro: 56.0 (#46)
- Step 3.5 Flash: 39.6 (#132)

| Benchmark | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| LMArena Expert | 1452 | 1421 |
| GPQA Diamond | 85.3% | — |
| Humanity's Last Exam | 21.6% | — |
| MMLU-Pro | 86.3% | — |
| Confabulations | 10.6% | — |
| Vectara Hallucination Rate | 7% | — |
| GPQA (HELM) | 74.9% | — |

## Multimodal

- Gemini 2.5 Pro: 45.2 (#18)
- Step 3.5 Flash: —

| Benchmark | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| LMArena Vision | 1263 | — |
| GeoBench | 86% | — |
| VPCT | 48% | — |
| LMArena Document | 1421 | — |
| SpatialViz-Bench | 44.7% | — |

## Multilingual

- Gemini 2.5 Pro: 55.3 (#31)
- Step 3.5 Flash: 50.5 (#119)

| Benchmark | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| LMArena Non-English | 1451 | 1385 |
| LMArena Chinese | 1507 | 1447 |
| LMArena French | 1472 | 1421 |
| LMArena German | 1487 | 1405 |
| LMArena Japanese | 1461 | 1354 |
| LMArena Korean | 1434 | 1352 |
| LMArena Russian | 1461 | 1385 |
| LMArena Spanish | 1473 | 1419 |

## Instruction Following

- Gemini 2.5 Pro: 75.0 (#75)
- Step 3.5 Flash: 73.1 (#124)

| Benchmark | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| LMArena Instruction Following | 1437 | 1385 |
| LiveBench Instruction Following | 80.6% | — |
| IFEval | 84% | — |

## Long Context

- Gemini 2.5 Pro: 59.8 (#5)
- Step 3.5 Flash: 42.8 (#117)

| Benchmark | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| LMArena Longer Query | 1449 | 1402 |
| Fiction.LiveBench | 91.7% | — |

## Writing & Preference

- Gemini 2.5 Pro: 63.7 (#62)
- Step 3.5 Flash: 58.8 (#113)

| Benchmark | Gemini 2.5 Pro | Step 3.5 Flash |
|---|---|---|
| LMArena Text | 1458 | 1403 |
| LMArena Creative Writing | 1454 | 1357 |
| LMArena Multi-Turn | 1453 | 1405 |
| Short-Story Creative Writing | 83.8% | — |
| EQ-Bench Creative Writing | 1421 | — |
| WildBench | 85.7% | — |
| LiveBench Language | 67.8% | — |

## FAQ

### Is Gemini 2.5 Pro better than Step 3.5 Flash?

Gemini 2.5 Pro is the stronger model overall, scoring 45.0 to 42.3 on the Noometry Index. Step 3.5 Flash costs 23× less per token, which makes it the better buy when Gemini 2.5 Pro's lead doesn't matter for your workload.

### Which is cheaper, Gemini 2.5 Pro or Step 3.5 Flash?

Step 3.5 Flash is cheaper. It lists at $0.10 per million input tokens and $0.30 per million output tokens; Gemini 2.5 Pro lists at $1.25 and $10.

### Is Gemini 2.5 Pro or Step 3.5 Flash better for coding?

They score almost the same on coding (42.4 vs 42.4); test both on your own repository before choosing.

### Which has the bigger context window?

Gemini 2.5 Pro does, with 1.05M tokens against 256K.

### How many benchmarks do Gemini 2.5 Pro and Step 3.5 Flash share?

17 benchmarks have published results for both models. Gemini 2.5 Pro has 78 scored results on Noometry and Step 3.5 Flash has 19.