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Gemini 3.1 Pro vs Gemini 3.6 Flash

Gemini 3.1 Pro and Gemini 3.6 Flash are closely matched at 43.3 and 43.3 on the LLM Stats Score. Gemini 3.6 Flash is 1.5x cheaper per token.

Google · Google · Updated for 2026

Which is better?

Gemini 3.1 Pro and Gemini 3.6 Flash are closely matched on the overall LLM Stats Score at 43.3 and 43.3.

In the 3 individual benchmarks reported for both models, Gemini 3.6 Flash wins 3; this is a narrower head-to-head signal than the composite indexes.

On price, Gemini 3.6 Flash is roughly 1.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Gemini 3.6 Flash 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 3.1 Pro

  • you want predictable pricing at $2.00/M input and $12.00/M output

Choose Gemini 3.6 Flash

  • you value its reported benchmark strengths — it wins 3 of 3 exact shared results
  • cost matters — it's about 1.5x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Jul 2026

At a glance

The differences that matter most.

Gemini 3.1 Pro
Google
Gemini 3.6 Flash
Google
Core performance indexes
LLM Stats Score
43.3
#39
43.3
#40
Reasoning
45.0
#30
40.0
#54
Coding
31.2
#44
28.8
#56
Agents
24.4
#52
27.8
#41
Cost, coverage & limits
Benchmark wins
0 of 3
3 of 3
Input price
$2.00 / M
$1.50 / M
Output price
$12.00 / M
$7.50 / M
Context window
1,000,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Gemini 3.1 Pro
Gemini 3.6 Flash
Vision
31.0#27
31.9#23
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

20 reported for Gemini 3.1 Pro · 7 for Gemini 3.6 Flash

3 shared

Gemini 3.1 Pro outperforms in 0 benchmarks, while Gemini 3.6 Flash is better at 3 benchmarks (DeepSWE 1.1, MRCR v2 (8-needle), SWE-Bench Pro).

Gemini 3.6 Flash significantly outperforms across most benchmarks.

Sun Sep 20 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Gemini 3.6 Flash costs less

For input processing, Gemini 3.1 Pro ($2.00/1M tokens) is 1.3x more expensive than Gemini 3.6 Flash ($1.50/1M tokens).

For output processing, Gemini 3.1 Pro ($12.00/1M tokens) is 1.6x more expensive than Gemini 3.6 Flash ($7.50/1M tokens).

In conclusion, Gemini 3.1 Pro is more expensive than Gemini 3.6 Flash.*

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

Lowest available price from all providers
Sun Sep 20 2026 • llm-stats.com
Google
Gemini 3.1 Pro
Input tokens$2.00
Output tokens$12.00
Best providerDeepinfra
Google
Gemini 3.6 Flash
Input tokens$1.50
Output tokens$7.50
Best providerGoogle
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 3.6 Flash accepts 1,048,576 input tokens compared to Gemini 3.1 Pro's 1,000,000 tokens. Gemini 3.1 Pro can generate longer responses up to 1,000,000 tokens, while Gemini 3.6 Flash is limited to 65,536 tokens.

Google
Gemini 3.1 Pro
Input1,000,000 tokens
Output1,000,000 tokens
Google
Gemini 3.6 Flash
Input1,048,576 tokens
Output65,536 tokens
Sun Sep 20 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Gemini 3.1 Pro and Gemini 3.6 Flash 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

Gemini 3.6 Flash

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

Gemini 3.6 Flash

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.1 Pro was released on 2026-02-19, while Gemini 3.6 Flash was released on 2026-07-21.

Gemini 3.6 Flash is 5 months newer than Gemini 3.1 Pro.

Gemini 3.1 Pro

Feb 19, 2026

7 months ago

Gemini 3.6 Flash

Jul 21, 2026

2 months ago

5mo newer

Knowledge Cutoff

When training data ends

Gemini 3.1 Pro has a knowledge cutoff of 2025-01-31, while Gemini 3.6 Flash has a cutoff of 2026-03-31.

Gemini 3.6 Flash has more recent training data (up to 2026-03-31), making it potentially better informed about events through that date compared to Gemini 3.1 Pro (2025-01-31).

Gemini 3.1 Pro

Jan 2025

Gemini 3.6 Flash

Mar 2026

1.2 yr newer

Provider Availability

Gemini 3.1 Pro is available from DeepInfra, Google. Gemini 3.6 Flash is available from Google.

Gemini 3.1 Pro

deepinfra logo
Deepinfra
Input Price:Input: $2.00/1MOutput Price:Output: $12.00/1M
google logo
Google
Input Price:Input: $2.50/1MOutput Price:Output: $15.00/1M

Gemini 3.6 Flash

google logo
Google
Input Price:Input: $1.50/1MOutput Price:Output: $7.50/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Gemini 3.1 Pro and Gemini 3.6 Flash side-by-side, then vote on the output you prefer.

Gemini 3.1 Pro
✓ Preferred
Gemini 3.6 Flash
Open in Playground

FAQ

Common questions about Gemini 3.1 Pro vs Gemini 3.6 Flash.

Which is better, Gemini 3.1 Pro or Gemini 3.6 Flash?

Gemini 3.1 Pro and Gemini 3.6 Flash are closely matched on the LLM Stats Score at 43.3 and 43.3. Gemini 3.1 Pro is made by Google and Gemini 3.6 Flash is made by Google. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Gemini 3.1 Pro compare to Gemini 3.6 Flash in benchmarks?

Gemini 3.1 Pro scores t2-bench: 99.3%, LiveCodeBench Pro: 96.2%, GPQA: 94.3%, MMMLU: 92.6%, BrowseComp: 85.9%. Gemini 3.6 Flash scores CharXiv-R: 89.4%, OSWorld-Verified: 83.0%, Terminal-Bench 2.1: 78.0%, MLE-Bench: 63.9%, SWE-Bench Pro: 58.7%.

Is Gemini 3.1 Pro cheaper than Gemini 3.6 Flash?

Gemini 3.6 Flash is 1.3x cheaper for input tokens. Gemini 3.1 Pro costs $2.00/M input and $12.00/M output via deepinfra. Gemini 3.6 Flash costs $1.50/M input and $7.50/M output via google.

What are the context window sizes for Gemini 3.1 Pro and Gemini 3.6 Flash?

Gemini 3.1 Pro supports 1.0M tokens and Gemini 3.6 Flash supports 1.0M 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 Gemini 3.6 Flash?

Key differences include LLM Stats Score (43.3 vs 43.3), context window (1.0M vs 1.0M), input pricing ($2.00 vs $1.50/M). See the full comparison above for benchmark-by-benchmark results.

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