Model Comparison

Gemini 3.6 Flash vs GPT-5.1 InstantWhich is better in 2026?

Comparing Gemini 3.6 Flash and GPT-5.1 Instant across benchmarks, pricing, and capabilities.

Verdict: Gemini 3.6 Flash vs GPT-5.1 Instant — which is better?

Gemini 3.6 Flash (by Google) and GPT-5.1 Instant (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, Gemini 3.6 Flash is roughly 1.1x 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.

Choose Gemini 3.6 Flash if…

  • cost matters — it's about 1.1x 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

Choose GPT-5.1 Instant if…

  • you want predictable pricing at $1.25/M input and $10.00/M output

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

Gemini 3.6 Flash and GPT-5.1 Instantdon'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

Gemini 3.6 Flash costs less

For input processing, Gemini 3.6 Flash ($1.50/1M tokens) is 1.2x more expensive than GPT-5.1 Instant ($1.25/1M tokens).

For output processing, Gemini 3.6 Flash ($7.50/1M tokens) is 1.3x cheaper than GPT-5.1 Instant ($10.00/1M tokens).

In conclusion, GPT-5.1 Instant is more expensive than Gemini 3.6 Flash.*

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

Lowest available price from all providers
Thu Jul 23 2026 • llm-stats.com
Google
Gemini 3.6 Flash
Input tokens$1.50
Output tokens$7.50
Best providerGoogle
OpenAI
GPT-5.1 Instant
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 3.6 Flash 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 3.6 Flash is limited to 65,536 tokens.

Google
Gemini 3.6 Flash
Input1,048,576 tokens
Output65,536 tokens
OpenAI
GPT-5.1 Instant
Input400,000 tokens
Output128,000 tokens
Thu Jul 23 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Gemini 3.6 Flash and GPT-5.1 Instant support multimodal inputs.

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

Gemini 3.6 Flash

Text
Images
Audio
Video

GPT-5.1 Instant

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 3.6 Flash

Proprietary

Closed source

GPT-5.1 Instant

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.6 Flash was released on 2026-07-21, while GPT-5.1 Instant was released on 2025-11-12.

Gemini 3.6 Flash is 8 months newer than GPT-5.1 Instant.

Gemini 3.6 Flash

Jul 21, 2026

2 days ago

8mo newer
GPT-5.1 Instant

Nov 12, 2025

8 months ago

Knowledge Cutoff

When training data ends

Gemini 3.6 Flash has a documented knowledge cutoff of 2026-03-31, while GPT-5.1 Instant's cutoff date is not specified.

We can confirm Gemini 3.6 Flash's training data extends to 2026-03-31, but cannot make a direct comparison without GPT-5.1 Instant's cutoff date.

Gemini 3.6 Flash

Mar 2026

GPT-5.1 Instant

—

Provider Availability

Gemini 3.6 Flash is available from Google. GPT-5.1 Instant is available from OpenAI.

Gemini 3.6 Flash

google logo
Google
Input Price:Input: $1.50/1MOutput Price:Output: $7.50/1M

GPT-5.1 Instant

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)
Less expensive output tokens
OpenAI
Less expensive input tokens

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Gemini 3.6 Flash and GPT-5.1 Instant side-by-side, then vote on the output you prefer.

Gemini 3.6 Flash
✓ Preferred
GPT-5.1 Instant
Open in Playground
AI Model Comparison Table
Feature
Google
Gemini 3.6 Flash
OpenAI
GPT-5.1 Instant

FAQ

Common questions about Gemini 3.6 Flash vs GPT-5.1 Instant.

Which is better, Gemini 3.6 Flash or GPT-5.1 Instant?

Gemini 3.6 Flash (Google) and GPT-5.1 Instant (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 3.6 Flash compare to GPT-5.1 Instant in benchmarks?

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%. GPT-5.1 Instant scores Tau2 Telecom: 95.6%, AIME 2025: 94.0%, BrowseComp Long Context 128k: 90.0%, GPQA: 88.1%, MMMU: 85.4%.

Is Gemini 3.6 Flash cheaper than GPT-5.1 Instant?

GPT-5.1 Instant is 1.2x cheaper for input tokens. Gemini 3.6 Flash costs $1.50/M input and $7.50/M output via google. GPT-5.1 Instant costs $1.25/M input and $10.00/M output via openai.

What are the context window sizes for Gemini 3.6 Flash and GPT-5.1 Instant?

Gemini 3.6 Flash supports 1.0M tokens and GPT-5.1 Instant 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 3.6 Flash and GPT-5.1 Instant?

Key differences include context window (1.0M vs 400K), input pricing ($1.50 vs $1.25/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3.6 Flash and GPT-5.1 Instant?

Gemini 3.6 Flash is developed by Google and GPT-5.1 Instant is developed by OpenAI.

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