Gemini 2.5 Pro vs GPT-5.1 Thinking
GPT-5.1 Thinking leads the LLM Stats Score 36.8 to 27.8. Gemini 2.5 Pro and GPT-5.1 Thinking cost the same.
Google · OpenAI · Updated for 2026
Which is better?
GPT-5.1 Thinking leads the overall LLM Stats Score 36.8 to 27.8, ranking #69 overall.
In the 4 individual benchmarks reported for both models, GPT-5.1 Thinking wins 4; this is a narrower head-to-head signal than the composite indexes.
Gemini 2.5 Pro also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Gemini 2.5 Pro
- you process long inputs — it offers a 1,048,576 token context window
Choose GPT-5.1 Thinking
- overall performance matters — it scores 36.8 and ranks #69 on LLM Stats
- your work emphasizes reasoning — it leads those capability indexes
- you value its reported benchmark strengths — it wins 4 of 4 exact shared results
- you want the most recent training data — it shipped Nov 2025
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
16 reported for Gemini 2.5 Pro · 9 for GPT-5.1 Thinking
Gemini 2.5 Pro outperforms in 0 benchmarks, while GPT-5.1 Thinking is better at 4 benchmarks (AIME 2025, GPQA, MMMU, SWE-Bench Verified).
GPT-5.1 Thinking significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Gemini 2.5 Pro ($1.25/1M tokens) costs the same as GPT-5.1 Thinking ($1.25/1M tokens).
For output processing, Gemini 2.5 Pro ($10.00/1M tokens) costs the same as GPT-5.1 Thinking ($10.00/1M tokens).
In conclusion, Gemini 2.5 Pro and GPT-5.1 Thinking cost the same.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Gemini 2.5 Pro accepts 1,048,576 input tokens compared to GPT-5.1 Thinking's 400,000 tokens. GPT-5.1 Thinking can generate longer responses up to 128,000 tokens, while Gemini 2.5 Pro is limited to 65,536 tokens.
Input capabilities
Documented input modalities across available providers
Both Gemini 2.5 Pro and GPT-5.1 Thinking support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Gemini 2.5 Pro
GPT-5.1 Thinking
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 2.5 Pro was released on 2025-05-20, while GPT-5.1 Thinking was released on 2025-11-12.
GPT-5.1 Thinking is 6 months newer than Gemini 2.5 Pro.
May 20, 2025
1.3 years ago
Nov 12, 2025
9 months ago
5mo newerKnowledge Cutoff
When training data ends
Gemini 2.5 Pro has a documented knowledge cutoff of 2025-01-31, while GPT-5.1 Thinking's cutoff date is not specified.
We can confirm Gemini 2.5 Pro's training data extends to 2025-01-31, but cannot make a direct comparison without GPT-5.1 Thinking's cutoff date.
Jan 2025
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Provider Availability
Gemini 2.5 Pro is available from Google. GPT-5.1 Thinking is available from OpenAI.
Gemini 2.5 Pro
GPT-5.1 Thinking
Outputs Comparison
Judge for yourself.
Run your own prompts against Gemini 2.5 Pro and GPT-5.1 Thinking side-by-side, then vote on the output you prefer.
FAQ
Common questions about Gemini 2.5 Pro vs GPT-5.1 Thinking.