Model Comparison

Gemini 3.1 Pro vs GPT-5.1 MediumWhich is better in 2026?

Comparing Gemini 3.1 Pro and GPT-5.1 Medium across benchmarks, pricing, and capabilities.

Verdict: Gemini 3.1 Pro vs GPT-5.1 Medium — which is better?

Gemini 3.1 Pro (by Google) and GPT-5.1 Medium (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.

On price, GPT-5.1 Medium is roughly 1.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Gemini 3.1 Pro also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

Choose Gemini 3.1 Pro if…

  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Feb 2026

Choose GPT-5.1 Medium if…

  • cost matters — it's about 1.6x cheaper per token
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Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

Gemini 3.1 Pro and GPT-5.1 Mediumdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT-5.1 Medium costs less

For input processing, Gemini 3.1 Pro ($2.50/1M tokens) is 2.0x more expensive than GPT-5.1 Medium ($1.25/1M tokens).

For output processing, Gemini 3.1 Pro ($15.00/1M tokens) is 1.5x more expensive than GPT-5.1 Medium ($10.00/1M tokens).

In conclusion, Gemini 3.1 Pro is more expensive than GPT-5.1 Medium.*

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

Lowest available price from all providers
Wed Jun 24 2026 • llm-stats.com
Google
Gemini 3.1 Pro
Input tokens$2.50
Output tokens$15.00
Best providerGoogle
OpenAI
GPT-5.1 Medium
Input tokens$1.25
Output tokens$10.00
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-5.1 Medium's 400,000 tokens. GPT-5.1 Medium 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-5.1 Medium
Input400,000 tokens
Output128,000 tokens
Wed Jun 24 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Gemini 3.1 Pro and GPT-5.1 Medium 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-5.1 Medium

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-5.1 Medium

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.1 Pro was released on 2026-02-19, while GPT-5.1 Medium was released on 2025-11-12.

Gemini 3.1 Pro is 3 months newer than GPT-5.1 Medium.

Gemini 3.1 Pro

Feb 19, 2026

4 months ago

3mo newer
GPT-5.1 Medium

Nov 12, 2025

7 months ago

Knowledge Cutoff

When training data ends

Gemini 3.1 Pro has a documented knowledge cutoff of 2025-01-31, while GPT-5.1 Medium'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-5.1 Medium's cutoff date.

Gemini 3.1 Pro

Jan 2025

GPT-5.1 Medium

—

Provider Availability

Gemini 3.1 Pro is available from Google. GPT-5.1 Medium is available from OpenAI.

Gemini 3.1 Pro

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

GPT-5.1 Medium

openai logo
OpenAI
Input Price:Input: $1.25/1MOutput Price:Output: $10.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Google
Larger context window (1,048,576 tokens)
OpenAI
Less expensive input tokens
Less expensive output tokens

Detailed Comparison

AI Model Comparison Table
Feature
Google
Gemini 3.1 Pro
OpenAI
GPT-5.1 Medium

FAQ

Common questions about Gemini 3.1 Pro vs GPT-5.1 Medium.

Which is better, Gemini 3.1 Pro or GPT-5.1 Medium?

Gemini 3.1 Pro (Google) and GPT-5.1 Medium (OpenAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does Gemini 3.1 Pro compare to GPT-5.1 Medium in benchmarks?

Gemini 3.1 Pro scores t2-bench: 99.3%, LiveCodeBench Pro: 96.2%, GPQA: 94.3%, MMMLU: 92.6%, BrowseComp: 85.9%. GPT-5.1 Medium scores AIME 2025: 98.4%.

Is Gemini 3.1 Pro cheaper than GPT-5.1 Medium?

GPT-5.1 Medium is 2.0x cheaper for input tokens. Gemini 3.1 Pro costs $2.50/M input and $15.00/M output via google. GPT-5.1 Medium costs $1.25/M input and $10.00/M output via openai.

What are the context window sizes for Gemini 3.1 Pro and GPT-5.1 Medium?

Gemini 3.1 Pro supports 1.0M tokens and GPT-5.1 Medium supports 400K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Gemini 3.1 Pro and GPT-5.1 Medium?

Key differences include context window (1.0M vs 400K), input pricing ($2.50 vs $1.25/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3.1 Pro and GPT-5.1 Medium?

Gemini 3.1 Pro is developed by Google and GPT-5.1 Medium is developed by OpenAI.

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