Compare / head-to-head
Gemini 3.5 FlashvsGPT-5.5
Gemini 3.5 Flash and GPT-5.5 split their 8 shared benchmarks evenly. Gemini 3.5 Flash is 3.3x cheaper per token. Gemini 3.5 Flash has the larger context window (1.0M tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
4 – 4
even split
Cheaper per token
Gemini 3.5 Flash
3.3x cheaper, input + output
Larger context
Gemini 3.5 Flash
1.0M tokens
Provider uptime (30d)
100% · 95.2096%
Google · OpenAI
Gemini 3.5 Flash
Google · released 2026-05-19
textvisionaudio
Quality
Benchmark matrix
8 shared · 7 only Gemini 3.5 Flash · 13 only GPT-5.5| Benchmark | Gemini 3.5 Flash | GPT-5.5 | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 8 | ||||
| GPQA Diamond | 92.8% ↗epoch | 90.7% ↗epoch | +2.1 pt | Gemini 3.5 Flash |
| AIME 2026 | 95% ↗matharena ⚠ | 100% ↗matharena ⚠ | -5 pt | GPT-5.5 |
| FrontierMath Tier 4 v2 (Epoch AI run) | 26.8% ↗epoch | 72.5% ↗epoch | -45.7 pt | GPT-5.5 |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 62.8% ↗epoch | 85.3% ↗epoch | -22.5 pt | GPT-5.5 |
| MCP Atlas | 83.6% ↗ | 75.3% ↗ | +8.3 pt | Gemini 3.5 Flash |
| OSWorld-Verified | 78.4% ↗ | 78.7% ↗ | -0.3 pt | GPT-5.5 |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 95.6% ↗epoch | 84.4% ↗epoch | +11.2 pt | Gemini 3.5 Flash |
| SimpleQA Verified | 66.2% ↗epoch | 63% ↗epoch | +3.2 pt | Gemini 3.5 Flash |
| Only Gemini 3.5 Flash reports · 7 | ||||
| ARC-AGI-2 | 72.1% ↗ | not reported | — | — |
| GDPVal-AA | 1656 ↗ | not reported | — | — |
| Humanity's Last Exam (full set, text + MM) | 40.2% ↗ | not reported | — | — |
| MMMU-Pro | 83.6% ↗ | not reported | — | — |
| SWE-Bench Pro (Public) | 55.1% ↗ | not reported | — | — |
| SWE-bench Verified (Epoch AI run) | 79.3% ↗epoch | not reported | — | — |
| Terminal-bench 2.1 | 76.2% ↗ | not reported | — | — |
| Only GPT-5.5 reports · 13 | ||||
| LMArena Elo | not reported | 1465.6 ↗ | — | — |
| ARC-AGI-1 (Verified) | not reported | 95% ↗ | — | — |
| ARC-AGI-2 (Verified) | not reported | 85% ↗ | — | — |
| BrowseComp | not reported | 84.4% ↗ | — | — |
| FrontierMath Tier 1-3 | not reported | 51.7% ↗ | — | — |
| FrontierMath Tier 4 | not reported | 35.4% ↗ | — | — |
| GDPval (wins or ties) | not reported | 84.9% ↗ | — | — |
| MMMU-Pro (no tools) | not reported | 81.2% ↗ | — | — |
| MMMU-Pro (with tools) | not reported | 83.2% ↗ | — | — |
| SWE-Bench Pro | not reported | 58.6% ↗ | — | — |
| Tau2-bench Telecom | not reported | 98% ↗ | — | — |
| Terminal-Bench 2.0 | not reported | 82.7% ↗ | — | — |
| Toolathlon | not reported | 55.6% ↗ | — | — |
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 3.5 Flash minus GPT-5.5 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 3.5 Flash | GPT-5.5 | Edge |
|---|---|---|---|
| Context window | 1.0M tokens | 1M tokens | Gemini 3.5 Flash |
| Max output | 66K tokens | 128K tokens | GPT-5.5 |
| Input price / 1M | $1.5 ↗ | $5 ↗ | Gemini 3.5 Flash |
| Output price / 1M | $9 ↗ | $30 ↗ | Gemini 3.5 Flash |
| Cached input / 1M | $0.15 ↗ | $0.5 ↗ | Gemini 3.5 Flash |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $10.5 | $35 | Gemini 3.5 Flash |
| Modalities | text · vision · audio | text · vision | Gemini 3.5 Flash |
| Released | 2026-05-19 | 2026-04-23 | — |
| Cited benchmark scores | 15 | 21 | — |
Reliability
Provider status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
Gemini 3.5 Flash vs …
Models sharing the most benchmarksMore matchups
GPT-5.5 vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
Public benchmarks are a starting point. Run Gemini 3.5 Flash and GPT-5.5 on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.