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FLUX.1 Fill [pro] vs Gemini 3.1 Flash Image

Comparing FLUX.1 Fill [pro] and Gemini 3.1 Flash Image across benchmarks, pricing, and capabilities.

Black Forest Labs · Google · Updated for 2026

Which is better?

FLUX.1 Fill [pro] and Gemini 3.1 Flash Image trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

Gemini 3.1 Flash Image also accepts a larger context window (65,536 input tokens), making it the stronger choice for long documents and large codebases.

Based on current benchmark, pricing, and model metadata for 2026.

Choose FLUX.1 Fill [pro]

  • you are already invested in the Black Forest Labs ecosystem

Choose Gemini 3.1 Flash Image

  • you process long inputs — it offers a 65,536 token context window

At a glance

The differences that matter most.

FLUX.1 Fill [pro]
Black Forest Labs
Gemini 3.1 Flash Image
Google
Benchmark wins
—
—
Input price
— / M
$0.50 / M
Output price
— / M
$30.00 / M
Context window
2,000
65,536
Released
—
Feb 2026
License
Proprietary
Proprietary

Arena Performance

Human preference votes

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

FLUX.1 Fill [pro]

Proprietary

Closed source

Gemini 3.1 Flash Image

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.1 Flash Image was released on 2026-02-26, while FLUX.1 Fill [pro]'s release date is not specified.

We can confirm Gemini 3.1 Flash Image's release timeline, but cannot make a direct age comparison without FLUX.1 Fill [pro]'s release date.

FLUX.1 Fill [pro]

—

Gemini 3.1 Flash Image

Feb 26, 2026

6 months ago

Provider Availability

FLUX.1 Fill [pro] is available from Fal. Gemini 3.1 Flash Image is available from Google.

FLUX.1 Fill [pro]

fal logo
Fal

Gemini 3.1 Flash Image

google logo
Google
Input Price:Input: $0.50/1MOutput Price:Output: $30.00/1M
* Prices shown are per million tokens

Outputs Comparison

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Judge for yourself.

Run your own prompts against FLUX.1 Fill [pro] and Gemini 3.1 Flash Image side-by-side, then vote on the output you prefer.

FLUX.1 Fill [pro]
✓ Preferred
Gemini 3.1 Flash Image
Open in Playground

FAQ

Common questions about FLUX.1 Fill [pro] vs Gemini 3.1 Flash Image.

Which is better, FLUX.1 Fill [pro] or Gemini 3.1 Flash Image?

FLUX.1 Fill [pro] (Black Forest Labs) and Gemini 3.1 Flash Image (Google) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

What are the context window sizes for FLUX.1 Fill [pro] and Gemini 3.1 Flash Image?

FLUX.1 Fill [pro] supports 2K tokens and Gemini 3.1 Flash Image supports 66K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between FLUX.1 Fill [pro] and Gemini 3.1 Flash Image?

Key differences include context window (2K vs 66K), multimodal support (no vs yes). See the full comparison above for benchmark-by-benchmark results.

Who makes FLUX.1 Fill [pro] and Gemini 3.1 Flash Image?

FLUX.1 Fill [pro] is developed by Black Forest Labs and Gemini 3.1 Flash Image is developed by Google.

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