Gemini 3 Pro Preview vs Gemini 3.1 Pro Preview

Wins 1 of 5 benchmarks
$1.30 / task
Wins 2 of 5 benchmarks
Different efforts: high · thinking · Compare all at high
Humanity's Last Exam Humanity's Last Exam: Very hard expert questions across many fields, written to stump today’s models
Gemini 3 Pro Preview39.7
Gemini 3.1 Pro Preview47
Terminal-Bench 4.0 Terminal-Bench 4.0 · source setting 2: Agents use a terminal to complete executable coding, system administration and research tasks in the 4.0 suite
Gemini 3 Pro Preview—
Gemini 3.1 Pro Preview4
AutomationBench-AA AutomationBench-AA: Agents orchestrate SaaS workflows through APIs; objectives receive credit only when the task has no guardrail violation
Gemini 3 Pro Preview—
Gemini 3.1 Pro Preview35.4
Arena Text · creative writing Arena Text · creative writing: Human pairwise preferences in the stated text vote pool
Gemini 3 Pro Preview1,485
Gemini 3.1 Pro Preview1,481
MMMU-Pro (vision) MMMU-Pro (vision): College-level questions that require understanding images: charts, diagrams, photos
Gemini 3 Pro Preview80.2
Gemini 3.1 Pro Preview82.4

Specs

SpecGemini 3 Pro PreviewGemini 3.1 Pro Preview
Input, per 1M!$2$2
Output, per 1M!$12$12
Cost per task?—$1.30
Speed, tok/s—115
Context1M1M
WeightsClosedClosed
ReleasedNov 2025Feb 2026
See images✓✓
Read PDFsPartial✓
Hear audio✓✓
Watch video✓✓
Call tools✓✓
Force a tool call?Partial
Return strict JSON✓✓
Search the web?✓
Run code?✓
Use a computer??

What breaks when you switch

Gemini 3 Pro Preview → Gemini 3.1 Pro Preview
Cannot use both thinking controls›

Setting thinking_level and legacy thinking_budget together returns HTTP 400; use only one.

Gemini 3.1 Pro Preview → Gemini 3 Pro Preview
Cannot use both thinking controls›

Setting thinking_level and legacy thinking_budget together returns HTTP 400; use only one.