Gemini 3.1 Pro vs Gemini 3 Flash vs GPT-5.5
Pick two to four models to compare benchmark scores, prices, context windows and speed. The link updates as you pick, so you can share the exact comparison.
Cheapest blended
Gemini 3 Flash
$1.13 / 1M tokens
Largest context
GPT-5.5
1.05M tokens
Fastest output
Gemini 3 Flash
182 tokens/s
Top on Humanity’s Last Exam (no tools)
Gemini 3.1 Pro
44.4%
Specifications
| Spec | Gemini 3.1 ProGoogle | Gemini 3 FlashGoogle | GPT-5.5OpenAI |
|---|---|---|---|
| Provider | OpenAI | ||
| Released | 19 Feb 2026 | 17 Dec 2025 | 24 Apr 2026 |
| Licence | ProprietaryPreview | ProprietaryPreview | Proprietary |
| Context window | 1.05M tokens | 1.05M tokens | 1.05M tokens |
| Max output | 66K tokens | 66K tokens | 128K tokens |
| Input / 1M | $2.00* | $0.50* | $5.00* |
| Output / 1M | $12.00 | $3.00 | $30.00 |
| Cached input / 1M | $0.20 | $0.05 | $0.50 |
| Speed | 114 tokens/s | 182 tokens/s | 86 tokens/s |
| Input types | text, image, video, audio, pdf | text, image, video, audio, pdf | text, image |
| Best for | ReasoningCodingAgentsMultimodal | Budget | CodingAgents |
* Gemini 3.1 Pro: Still preview. A separate endpoint, gemini-3.1-pro-preview-customtools, has the same price. Cache storage $4.50 per 1M tokens per hour. Priority is $3.60 / $21.60 up to 200K.
* Gemini 3 Flash: Audio input costs $1.00, or $0.10 cached. Cache storage $1.00 per 1M tokens per hour. Google calls it a legacy model; the deprecations page names gemini-3.6-flash as the replacement, with no shutdown date yet.
* GPT-5.5: There is no separate cache-write charge (pre-GPT-5.6 models). Batch and Flex: $2.50 / $15. Fast mode: 2.5x, $12.50 / $75. Snapshot gpt-5.5-2026-04-23. GPT-5.5 Pro (gpt-5.5-pro) costs $30 / $180. Data residency +10%.
Benchmark scores
Officially reported scores only. A model with no published score on a benchmark shows a line, not a zero.
Price per 1M tokens
Context window and speed
Notes
- Gemini 3.1 Pro
- Google's current Pro model, still preview. Built for multimodal understanding, agentic work and vibe-coding, with a focus on software engineering and multi-step tool use.
- Gemini 3 Flash
- Legacy Gemini 3 preview Flash model giving baseline speed and intelligence. It is still served, but newer GA Flash models replace it.
- GPT-5.5
- A frontier model for coding and complex professional work, the flagship before GPT-5.6.
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