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Model Comparison

Gemini 3.1 Pro vs GPT-5.5

GPT-5.5 significantly outperforms across most benchmarks. Gemini 3.1 Pro is 2.0x cheaper per token.

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Performance Benchmarks

Comparative analysis across standard metrics

9 benchmarks

Gemini 3.1 Pro outperforms in 2 benchmarks (BrowseComp, GPQA), while GPT-5.5 is better at 7 benchmarks (ARC-AGI v2, Humanity's Last Exam, MCP Atlas, MMMU-Pro, MRCR v2 (8-needle), SWE-Bench Pro, Terminal-Bench 2.0).

GPT-5.5 significantly outperforms across most benchmarks.

Thu Apr 23 2026 • llm-stats.com

Arena Performance

Human preference votes

CallingBox

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Pricing Analysis

Price comparison per million tokens

Gemini 3.1 Pro costs less

For input processing, Gemini 3.1 Pro ($2.50/1M tokens) is 2.0x cheaper than GPT-5.5 ($5.00/1M tokens).

For output processing, Gemini 3.1 Pro ($15.00/1M tokens) is 2.0x cheaper than GPT-5.5 ($30.00/1M tokens).

In conclusion, GPT-5.5 is more expensive than Gemini 3.1 Pro.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Thu Apr 23 2026 • llm-stats.com
Google
Gemini 3.1 Pro
Input tokens$2.50
Output tokens$15.00
Best providerGoogle
OpenAI
GPT-5.5
Input tokens$5.00
Output tokens$30.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 3.1 Pro accepts 1,048,576 input tokens compared to GPT-5.5's 1,000,000 tokens. GPT-5.5 can generate longer responses up to 128,000 tokens, while Gemini 3.1 Pro is limited to 65,536 tokens.

Google
Gemini 3.1 Pro
Input1,048,576 tokens
Output65,536 tokens
OpenAI
GPT-5.5
Input1,000,000 tokens
Output128,000 tokens
Thu Apr 23 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Gemini 3.1 Pro and GPT-5.5 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Gemini 3.1 Pro

Text
Images
Audio
Video

GPT-5.5

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Gemini 3.1 Pro

Proprietary

Closed source

GPT-5.5

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.1 Pro was released on 2026-02-19, while GPT-5.5 was released on 2026-04-23.

GPT-5.5 is 2 months newer than Gemini 3.1 Pro.

Gemini 3.1 Pro

Feb 19, 2026

2 months ago

GPT-5.5

Apr 23, 2026

0 days ago

2mo newer

Knowledge Cutoff

When training data ends

Gemini 3.1 Pro has a documented knowledge cutoff of 2025-01-31, while GPT-5.5's cutoff date is not specified.

We can confirm Gemini 3.1 Pro's training data extends to 2025-01-31, but cannot make a direct comparison without GPT-5.5's cutoff date.

Gemini 3.1 Pro

Jan 2025

GPT-5.5

—

Provider Availability

Gemini 3.1 Pro is available from Google. GPT-5.5 is available from OpenAI.

Gemini 3.1 Pro

google logo
Google
Input Price:Input: $2.50/1MOutput Price:Output: $15.00/1M

GPT-5.5

openai logo
OpenAI
Input Price:Input: $5.00/1MOutput Price:Output: $30.00/1M
* Prices shown are per million tokens

Outputs Comparison

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Key Takeaways

Google
Larger context window (1,048,576 tokens)
Less expensive input tokens
Less expensive output tokens
Higher BrowseComp score (85.9% vs 84.4%)
Higher GPQA score (94.3% vs 93.6%)
OpenAI
Higher ARC-AGI v2 score (85.0% vs 77.1%)
Higher Humanity's Last Exam score (52.2% vs 51.4%)
Higher MCP Atlas score (75.3% vs 69.2%)
Higher MMMU-Pro score (83.2% vs 80.5%)
Higher MRCR v2 (8-needle) score (74.0% vs 26.3%)
Higher SWE-Bench Pro score (58.6% vs 54.2%)
Higher Terminal-Bench 2.0 score (82.7% vs 68.5%)

Detailed Comparison

AI Model Comparison Table
Feature
Google
Gemini 3.1 Pro
OpenAI
GPT-5.5

FAQ

Common questions about Gemini 3.1 Pro vs GPT-5.5

GPT-5.5 significantly outperforms across most benchmarks. Gemini 3.1 Pro is made by Google and GPT-5.5 is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.
Gemini 3.1 Pro scores t2-bench: 99.3%, LiveCodeBench Pro: 96.2%, GPQA: 94.3%, MMMLU: 92.6%, BrowseComp: 85.9%. GPT-5.5 scores Tau2 Telecom: 98.0%, ARC-AGI: 95.0%, GPQA: 93.6%, ARC-AGI v2: 85.0%, GDPval-MM: 84.9%.
Gemini 3.1 Pro is 2.0x cheaper for input tokens. Gemini 3.1 Pro costs $2.50/M input and $15.00/M output via google. GPT-5.5 costs $5.00/M input and $30.00/M output via openai.
Gemini 3.1 Pro supports 1.0M tokens and GPT-5.5 supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.
Key differences include context window (1.0M vs 1.0M), input pricing ($2.50 vs $5.00/M). See the full comparison above for benchmark-by-benchmark results.
Gemini 3.1 Pro is developed by Google and GPT-5.5 is developed by OpenAI.