Model Comparison
Gemini 3.1 Pro vs GPT-5.5 Pro
GPT-5.5 Pro significantly outperforms across most benchmarks. Gemini 3.1 Pro is 12.0x cheaper per token.
Performance Benchmarks
Comparative analysis across standard metrics
Gemini 3.1 Pro outperforms in 0 benchmarks, while GPT-5.5 Pro is better at 2 benchmarks (BrowseComp, Humanity's Last Exam).
GPT-5.5 Pro significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, Gemini 3.1 Pro ($2.50/1M tokens) is 12.0x cheaper than GPT-5.5 Pro ($30.00/1M tokens).
For output processing, Gemini 3.1 Pro ($15.00/1M tokens) is 12.0x cheaper than GPT-5.5 Pro ($180.00/1M tokens).
In conclusion, GPT-5.5 Pro is more expensive than Gemini 3.1 Pro.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.5 Pro accepts 1,050,000 input tokens compared to Gemini 3.1 Pro's 1,048,576 tokens. GPT-5.5 Pro can generate longer responses up to 128,000 tokens, while Gemini 3.1 Pro is limited to 65,536 tokens.
Input Capabilities
Supported data types and modalities
Both Gemini 3.1 Pro and GPT-5.5 Pro support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Gemini 3.1 Pro
GPT-5.5 Pro
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Gemini 3.1 Pro was released on 2026-02-19, while GPT-5.5 Pro was released on 2026-04-23.
GPT-5.5 Pro is 2 months newer than Gemini 3.1 Pro.
Feb 19, 2026
2 months ago
Apr 23, 2026
2 weeks ago
2mo newerKnowledge Cutoff
When training data ends
Gemini 3.1 Pro has a knowledge cutoff of 2025-01-31, while GPT-5.5 Pro has a cutoff of 2025-12-01.
GPT-5.5 Pro has more recent training data (up to 2025-12-01), making it potentially better informed about events through that date compared to Gemini 3.1 Pro (2025-01-31).
Jan 2025
Dec 2025
11 mo newerProvider Availability
Gemini 3.1 Pro is available from Google. GPT-5.5 Pro is available from OpenAI.
Gemini 3.1 Pro
GPT-5.5 Pro
Outputs Comparison
Key Takeaways
GPT-5.5 Pro
View detailsOpenAI
Detailed Comparison
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FAQ
Common questions about Gemini 3.1 Pro vs GPT-5.5 Pro.