Compare · ModelsLive · 2 picked · head to head
Gemini 3.1 Pro Preview vs Step 3.5 Flash
Side by side · benchmarks, pricing, and signals you can act on.
Winner summary
Gemini 3.1 Pro Preview wins on 3/4 benchmarks
Gemini 3.1 Pro Preview wins 3 of 4 shared benchmarks. Leads in speed · arena.
Category leads
speed·Gemini 3.1 Pro Previewarena·Gemini 3.1 Pro Preview
Hype vs Reality
Attention vs performance
Gemini 3.1 Pro Preview
#74 by perf·no signal
Step 3.5 Flash
#9 by perf·#11 by attention
Best value
Step 3.5 Flash
47.6x better value than Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview
8.1 pts/$
$7.00/M
Step 3.5 Flash
384.5 pts/$
$0.20/M
Vendor risk
Mixed exposure
One or more vendors flagged
Google DeepMind
$4.00T·Tier 1
StepFun
$5.0B·Tier 1
Head to head
4 benchmarks · 2 models
Gemini 3.1 Pro PreviewStep 3.5 Flash
Artificial Analysis · Agentic Index
Step 3.5 Flash leads by +30.6
Artificial Analysis Agentic Index · a composite score measuring how well a model performs in agentic workflows · multi-step tool use, planning, error recovery, and autonomous task completion. Aggregates results from multiple agentic benchmarks including SWE-bench, tool-use tests, and planning evaluations. The canonical single-number metric for "how good is this model as an agent?"
Gemini 3.1 Pro Preview
21.4
Step 3.5 Flash
52.0
Artificial Analysis · Coding Index
Gemini 3.1 Pro Preview leads by +37.2
Artificial Analysis Coding Index · a composite score that aggregates performance across multiple coding benchmarks into a single index. Tracks code generation quality, debugging ability, multi-language competence, and real-world software engineering tasks. Used by Artificial Analysis to rank model coding capability in a normalized, comparable format. Useful for developers choosing between models for coding-heavy workloads.
Gemini 3.1 Pro Preview
68.8
Step 3.5 Flash
31.6
Artificial Analysis · Quality Index
Gemini 3.1 Pro Preview leads by +8.7
Gemini 3.1 Pro Preview
46.5
Step 3.5 Flash
37.8
Chatbot Arena Elo · Overall
Gemini 3.1 Pro Preview leads by +91.3
Gemini 3.1 Pro Preview
1486.4
Step 3.5 Flash
1395.2
Full benchmark table
| Benchmark | Gemini 3.1 Pro Preview | Step 3.5 Flash |
|---|---|---|
Artificial Analysis · Agentic Index Artificial Analysis Agentic Index · a composite score measuring how well a model performs in agentic workflows · multi-step tool use, planning, error recovery, and autonomous task completion. Aggregates results from multiple agentic benchmarks including SWE-bench, tool-use tests, and planning evaluations. The canonical single-number metric for "how good is this model as an agent?" | 21.4 | 52.0 |
Artificial Analysis · Coding Index Artificial Analysis Coding Index · a composite score that aggregates performance across multiple coding benchmarks into a single index. Tracks code generation quality, debugging ability, multi-language competence, and real-world software engineering tasks. Used by Artificial Analysis to rank model coding capability in a normalized, comparable format. Useful for developers choosing between models for coding-heavy workloads. | 68.8 | 31.6 |
Artificial Analysis · Quality Index | 46.5 | 37.8 |
Chatbot Arena Elo · Overall | 1486.4 | 1395.2 |
Pricing · per 1M tokens · projected $/mo at 10M tokens
| Model | Input | Output | Context | Projected $/mo |
|---|---|---|---|---|
| $2.00 | $12.00 | 1.0M tokens (~524 books) | $45.00 | |
| $0.10 | $0.30 | 262K tokens (~131 books) | $1.50 |