Compare / head-to-head
Gemini 3.1 Pro PreviewvsStep 3.5 Flash
Gemini 3.1 Pro Preview leads 2 of 2 shared benchmarks. Gemini 3.1 Pro Preview has the larger context window (1.0M tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
2 – 0
Gemini 3.1 Pro Preview leads
Cheaper per token
—
list price, input + output
Larger context
Gemini 3.1 Pro Preview
1.0M tokens
Provider uptime (30d)
100% · —
Google · StepFun
Gemini 3.1 Pro Preview
Google · released 2026-02-19
textvisionaudio
Step 3.5 Flash
StepFun · released 2026-02-12
text
- Context
- 256K
- Max out
- —
- Input /1M
- —
- Output /1M
- —
- Cached /1M
- —
- Scores
- 18 · 5 core
Quality
Benchmark matrix
2 shared · 7 only Gemini 3.1 Pro Preview · 15 only Step 3.5 Flash| Benchmark | Gemini 3.1 Pro Preview | Step 3.5 Flash | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 2 | ||||
| AIME 2026 | 98.3% ↗matharena ⚠ | 96.7% ↗matharena | +1.6 pt | Gemini 3.1 Pro Preview |
| LMArena Elo | 1480.1 ↗ | 1403.7 ↗ | +76.4 | Gemini 3.1 Pro Preview |
| Only Gemini 3.1 Pro Preview reports · 7 | ||||
| GPQA Diamond | 94.3% ↗ | not reported | — | — |
| ARC-AGI-2 | 77.1% ↗ | not reported | — | — |
| FrontierMath Tier 4 v2 (Epoch AI run) | 26.8% ↗epoch | not reported | — | — |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 59.6% ↗epoch | not reported | — | — |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 95.6% ↗epoch | not reported | — | — |
| SimpleQA Verified | 73.5% ↗epoch | not reported | — | — |
| SWE-Bench Pro | 54.2% ↗ | not reported | — | — |
| Only Step 3.5 Flash reports · 15 | ||||
| SWE-bench Verified | not reported | 74.4% ↗ | — | — |
| AIME 2025 | not reported | 97.3% ↗ | — | — |
| BrowseComp | not reported | 51.6% ↗ | — | — |
| BrowseComp (with context manager) | not reported | 69% ↗ | — | — |
| BrowseComp-ZH | not reported | 66.9% ↗ | — | — |
| BrowseComp-ZH (with context manager) | not reported | 73.7% ↗ | — | — |
| GAIA (no file) | not reported | 84.5% ↗ | — | — |
| HMMT 2025 (Feb/Nov average) | not reported | 96.2% ↗ | — | — |
| IMOAnswerBench | not reported | 85.4% ↗ | — | — |
| LiveCodeBench v6 | not reported | 86.4% ↗ | — | — |
| ResearchRubrics | not reported | 65.3% ↗ | — | — |
| Tau2-Bench | not reported | 88.2% ↗ | — | — |
| Terminal-Bench 2.0 | not reported | 51% ↗ | — | — |
| xbench-DeepSearch 2025.05 | not reported | 83.7% ↗ | — | — |
| xbench-DeepSearch 2025.10 | not reported | 56.3% ↗ | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Gemini 3.1 Pro Preview minus Step 3.5 Flash in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | Gemini 3.1 Pro Preview | Step 3.5 Flash | Edge |
|---|---|---|---|
| Context window | 1.0M tokens | 256K tokens | Gemini 3.1 Pro Preview |
| Max output | 66K tokens | — | — |
| Input price / 1M | $2 ↗ | — | — |
| Output price / 1M | $12 ↗ | — | — |
| Cached input / 1M | $0.2 ↗ | — | — |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $14 | — | — |
| Modalities | text · vision · audio | text | Gemini 3.1 Pro Preview |
| Released | 2026-02-19 | 2026-02-12 | — |
| Cited benchmark scores | 10 | 18 | — |
Reliability
Provider status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
Gemini 3.1 Pro Preview vs …
Models sharing the most benchmarksMore matchups
Step 3.5 Flash vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
Public benchmarks are a starting point. Run Gemini 3.1 Pro Preview and Step 3.5 Flash on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.