Gemini 3 Pro vs GPT-5.1 Instant
Gemini 3 Pro and GPT-5.1 Instant are closely matched at 38.4 and 36.7 on the LLM Stats Score. GPT-5.1 Instant is 1.3x cheaper per token.
Google · OpenAI · Updated for 2026
Which is better?
Gemini 3 Pro and GPT-5.1 Instant are closely matched on the overall LLM Stats Score at 38.4 and 36.7.
In the 3 individual benchmarks reported for both models, Gemini 3 Pro wins 2; this is a narrower head-to-head signal than the composite indexes.
On price, GPT-5.1 Instant is roughly 1.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Gemini 3 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 3 Pro
- you value its reported benchmark strengths — it wins 2 of 3 exact shared results
- you process long inputs — it offers a 1,048,576 token context window
- you want the most recent training data — it shipped Nov 2025
Choose GPT-5.1 Instant
- cost matters — it's about 1.3x cheaper per token
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
21 reported for Gemini 3 Pro · 9 for GPT-5.1 Instant
Gemini 3 Pro outperforms in 2 benchmarks (AIME 2025, GPQA), while GPT-5.1 Instant is better at 1 benchmark (SWE-Bench Verified).
Gemini 3 Pro shows notably better performance in the majority of benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Gemini 3 Pro ($2.00/1M tokens) is 1.6x more expensive than GPT-5.1 Instant ($1.25/1M tokens).
For output processing, Gemini 3 Pro ($12.00/1M tokens) is 1.2x more expensive than GPT-5.1 Instant ($10.00/1M tokens).
In conclusion, Gemini 3 Pro is more expensive than GPT-5.1 Instant.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Gemini 3 Pro accepts 1,048,576 input tokens compared to GPT-5.1 Instant's 400,000 tokens. GPT-5.1 Instant can generate longer responses up to 128,000 tokens, while Gemini 3 Pro is limited to 65,536 tokens.
Input capabilities
Documented input modalities across available providers
Both Gemini 3 Pro and GPT-5.1 Instant support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Gemini 3 Pro
GPT-5.1 Instant
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-5.1 Instant was released on 2025-11-12.
Gemini 3 Pro is 0 month newer than GPT-5.1 Instant.
Nov 18, 2025
10 months ago
6d newerNov 12, 2025
11 months ago
Knowledge Cutoff
When training data ends
Gemini 3 Pro has a documented knowledge cutoff of 2025-01-31, while GPT-5.1 Instant's cutoff date is not specified.
We can confirm Gemini 3 Pro's training data extends to 2025-01-31, but cannot make a direct comparison without GPT-5.1 Instant's cutoff date.
Jan 2025
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Provider Availability
Gemini 3 Pro is available from Google. GPT-5.1 Instant is available from OpenAI.
Gemini 3 Pro
GPT-5.1 Instant
Outputs Comparison
Judge for yourself.
Run your own prompts against Gemini 3 Pro and GPT-5.1 Instant side-by-side, then vote on the output you prefer.
FAQ
Common questions about Gemini 3 Pro vs GPT-5.1 Instant.