Model Comparison
Gemini 3 Pro vs GPT-5.5 ProWhich is better in 2026?
GPT-5.5 Pro significantly outperforms across most benchmarks. Gemini 3 Pro is 15.0x cheaper per token.
Verdict: Gemini 3 Pro vs GPT-5.5 Pro — which is better?
Gemini 3 Pro (by Google) and GPT-5.5 Pro (by OpenAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.
Gemini 3 Pro outperforms in 0 benchmarks, while GPT-5.5 Pro is better at 1 benchmark (Humanity's Last Exam). GPT-5.5 Pro significantly outperforms across most benchmarks.
On price, Gemini 3 Pro is roughly 15.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.5 Pro also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.
Choose Gemini 3 Pro if…
- cost matters — it's about 15.0x cheaper per token
Choose GPT-5.5 Pro if…
- you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
- you process long inputs — it offers a 1,050,000 token context window
- you want the most recent training data — it shipped Apr 2026
Performance Benchmarks
Comparative analysis across standard metrics
Gemini 3 Pro outperforms in 0 benchmarks, while GPT-5.5 Pro is better at 1 benchmark (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 Pro ($2.00/1M tokens) is 15.0x cheaper than GPT-5.5 Pro ($30.00/1M tokens).
For output processing, Gemini 3 Pro ($12.00/1M tokens) is 15.0x cheaper than GPT-5.5 Pro ($180.00/1M tokens).
In conclusion, GPT-5.5 Pro is more expensive than Gemini 3 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 Pro's 1,048,576 tokens. GPT-5.5 Pro can generate longer responses up to 128,000 tokens, while Gemini 3 Pro is limited to 65,536 tokens.
Input Capabilities
Supported data types and modalities
Both Gemini 3 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 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 Pro was released on 2025-11-18, while GPT-5.5 Pro was released on 2026-04-23.
GPT-5.5 Pro is 5 months newer than Gemini 3 Pro.
Nov 18, 2025
8 months ago
Apr 23, 2026
2 months ago
5mo newerKnowledge Cutoff
When training data ends
Gemini 3 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 Pro (2025-01-31).
Jan 2025
Dec 2025
11 mo newerProvider Availability
Gemini 3 Pro is available from Google. GPT-5.5 Pro is available from OpenAI.
Gemini 3 Pro
GPT-5.5 Pro
Outputs Comparison
Key Takeaways
Gemini 3 Pro
View detailsGPT-5.5 Pro
View detailsOpenAI
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against Gemini 3 Pro and GPT-5.5 Pro side-by-side, then vote on the output you prefer.
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FAQ
Common questions about Gemini 3 Pro vs GPT-5.5 Pro.