Compare / head-to-head
Gemini 3.1 Pro PreviewvsGPT-5.5 Pro
GPT-5.5 Pro leads 2 of 2 shared benchmarks. Gemini 3.1 Pro Preview is 15x cheaper per token. GPT-5.5 Pro has the larger context window (1.1M tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
0 – 2
GPT-5.5 Pro leads
Cheaper per token
Gemini 3.1 Pro Preview
15x cheaper, input + output
Larger context
GPT-5.5 Pro
1.1M tokens
Provider uptime (30d)
100% · 94.8553%
Google · OpenAI
Gemini 3.1 Pro Preview
Google · released 2026-02-19
textvisionaudio
GPT-5.5 Pro
OpenAI · released 2026-04-23
textvision
Quality
Benchmark matrix
2 shared · 7 only Gemini 3.1 Pro Preview · 6 only GPT-5.5 Pro| Benchmark | Gemini 3.1 Pro Preview | GPT-5.5 Pro | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 2 | ||||
| FrontierMath Tier 4 v2 (Epoch AI run) | 26.8% ↗epoch | 78% ↗epoch | -51.2 pt | GPT-5.5 Pro |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 59.6% ↗epoch | 87.7% ↗epoch | -28.1 pt | GPT-5.5 Pro |
| Only Gemini 3.1 Pro Preview reports · 7 | ||||
| GPQA Diamond | 94.3% ↗ | not reported | — | — |
| AIME 2026 | 98.3% ↗matharena ⚠ | not reported | — | — |
| LMArena Elo | 1480.1 ↗ | not reported | — | — |
| ARC-AGI-2 | 77.1% ↗ | 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 GPT-5.5 Pro reports · 6 | ||||
| Humanity's Last Exam (no tools) | not reported | 43.1% ↗ | — | — |
| BrowseComp | not reported | 90.1% ↗ | — | — |
| FrontierMath Tier 1-3 | not reported | 52.4% ↗ | — | — |
| FrontierMath Tier 4 | not reported | 39.6% ↗ | — | — |
| GDPval (wins or ties) | not reported | 82.3% ↗ | — | — |
| Humanity's Last Exam (with tools) | not reported | 57.2% ↗ | — | — |
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 GPT-5.5 Pro 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 | GPT-5.5 Pro | Edge |
|---|---|---|---|
| Context window | 1.0M tokens | 1.1M tokens | GPT-5.5 Pro |
| Max output | 66K tokens | 128K tokens | GPT-5.5 Pro |
| Input price / 1M | $2 ↗ | $30 ↗ | Gemini 3.1 Pro Preview |
| Output price / 1M | $12 ↗ | $180 ↗ | Gemini 3.1 Pro Preview |
| Cached input / 1M | $0.2 ↗ | — | — |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $14 | $210 | Gemini 3.1 Pro Preview |
| Modalities | text · vision · audio | text · vision | Gemini 3.1 Pro Preview |
| Released | 2026-02-19 | 2026-04-23 | — |
| Cited benchmark scores | 10 | 8 | — |
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
GPT-5.5 Pro 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 GPT-5.5 Pro on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.