# Gemini 3 Deep Think vs Step 3.5 Flash

> Step 3.5 Flash has enough public results to be ranked (#116); Gemini 3 Deep Think does not yet, so treat this comparison as directional.

- Canonical page: https://noometry.com/compare/gemini-3-deep-think-vs-step-3-5-flash
- Last updated: 2026-10-11
- Shared benchmarks: 0

## Summary

- The widest gap is in reasoning, where Gemini 3 Deep Think leads 70.2 to 22.2.
- Step 3.5 Flash has downloadable open weights; the other is API-only.

## Snapshot

| | Gemini 3 Deep Think | Step 3.5 Flash |
|---|---|---|
| Provider | Google | StepFun |
| Noometry Index | 58.3 | 42.3 |
| Rank | — | 116 |
| Context | — | 256K |
| Input $/M | — | $0.10 |
| Output $/M | — | $0.30 |
| Weights | Proprietary | Open |

## Coding

- Gemini 3 Deep Think: —
- Step 3.5 Flash: 42.4 (#105)

| Benchmark | Gemini 3 Deep Think | Step 3.5 Flash |
|---|---|---|
| LMArena Coding | — | 1436 |

## Reasoning

- Gemini 3 Deep Think: 70.2 (#14)
- Step 3.5 Flash: 22.2 (#202)

| Benchmark | Gemini 3 Deep Think | Step 3.5 Flash |
|---|---|---|
| ARC-AGI-2 | 84.6% | — |
| NYT Connections (extended) | — | 28.4% |
| ARC-AGI-1 | 96% | — |
| CritPt | 25.7% | — |
| LMArena Hard Prompts | — | 1411 |

## Math

- Gemini 3 Deep Think: —
- Step 3.5 Flash: 42.6 (#84)

| Benchmark | Gemini 3 Deep Think | Step 3.5 Flash |
|---|---|---|
| MathArena Final-Answer Competitions | — | 66.8% |
| LMArena Math | — | 1408 |

## Knowledge

- Gemini 3 Deep Think: —
- Step 3.5 Flash: 39.6 (#132)

| Benchmark | Gemini 3 Deep Think | Step 3.5 Flash |
|---|---|---|
| LMArena Expert | — | 1421 |

## Multilingual

- Gemini 3 Deep Think: —
- Step 3.5 Flash: 50.5 (#119)

| Benchmark | Gemini 3 Deep Think | Step 3.5 Flash |
|---|---|---|
| LMArena Non-English | — | 1385 |
| LMArena Chinese | — | 1447 |
| LMArena French | — | 1421 |
| LMArena German | — | 1405 |
| LMArena Japanese | — | 1354 |
| LMArena Korean | — | 1352 |
| LMArena Russian | — | 1385 |
| LMArena Spanish | — | 1419 |

## Instruction Following

- Gemini 3 Deep Think: —
- Step 3.5 Flash: 73.1 (#124)

| Benchmark | Gemini 3 Deep Think | Step 3.5 Flash |
|---|---|---|
| LMArena Instruction Following | — | 1385 |

## Long Context

- Gemini 3 Deep Think: —
- Step 3.5 Flash: 42.8 (#117)

| Benchmark | Gemini 3 Deep Think | Step 3.5 Flash |
|---|---|---|
| LMArena Longer Query | — | 1402 |

## Writing & Preference

- Gemini 3 Deep Think: —
- Step 3.5 Flash: 58.8 (#113)

| Benchmark | Gemini 3 Deep Think | Step 3.5 Flash |
|---|---|---|
| LMArena Text | — | 1403 |
| LMArena Creative Writing | — | 1357 |
| LMArena Multi-Turn | — | 1405 |

## FAQ

### Is Gemini 3 Deep Think better than Step 3.5 Flash?

Step 3.5 Flash has enough public results to be ranked (#116); Gemini 3 Deep Think does not yet, so treat this comparison as directional.

### How many benchmarks do Gemini 3 Deep Think and Step 3.5 Flash share?

0 benchmarks have published results for both models. Gemini 3 Deep Think has 3 scored results on Noometry and Step 3.5 Flash has 19.