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Model Comparison

FLUX.2 Klein 4B vs Nano Banana 2.1Which Is Better in 2026?

Black Forest Labs: FLUX.2 Klein 4B logoBlack Forest Labs•Google: Nano Banana 2.1 logoGoogle

FLUX.2 Klein 4B vs Nano Banana 2.1: which should you choose in 2026?

FLUX.2 Klein 4B (by Black Forest Labs) and Nano Banana 2.1 (by Google) are compared below. Here is how they stack up on benchmarks, price, and capabilities, and which one to pick in 2026.

There are not enough shared, protocol-compatible benchmark results to declare a performance leader.

Choose FLUX.2 Klein 4B if…

  • • your own prompt tests favor its output; shared comparable evidence does not identify a unique advantage

Choose Nano Banana 2.1 if…

  • • you need a model with explicit reasoning support

The benchmark count includes only results measured with a matching benchmark version and protocol. Arena scores are shown separately. Missing, preliminary, and incompatible data is not treated as a controlled win. Published point-score comparisons are labeled separately when protocol details are incomplete. For text-output models, the verdict also compares token pricing and context windows.

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Performance benchmarks

Every value links to its source. A dash means that no reviewed result is available for that exact model and protocol.

FLUX.2 Klein 4B and Nano Banana 2.1 benchmark results
BenchmarkFLUX.2 Klein 4BNano Banana 2.1
AutomationBench-AA

A 657-task benchmark of multi-step work across simulated SaaS applications in six business domains. The Artificial Analysis protocol reports a guardrail-aware score and is distinct from both the public Zapier split and the unrelated dynamic AutoBench framework.

Guardrail-aware score

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BrowseComp

A benchmark of difficult, verifiable information-seeking questions designed to measure an agent's ability to locate hard-to-find facts through web browsing.

Accuracy

——
OSWorld-Verified

A verified computer-use benchmark in which multimodal agents operate desktop applications and are graded from the resulting environment state.

Mean task reward

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SWE-Bench Verified

A human-validated subset of real GitHub issues used to measure whether a coding agent can produce repository patches that resolve the associated tests.

Resolved

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Terminal-Bench 2.1

Version 2.1 of the benchmark for completing realistic tasks in terminal environments. Harness, resource limits, and attempt count are part of the protocol.

Mean task success

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AutoBench

A dynamic LLM evaluation framework in which models generate questions, answer them, and participate in reciprocal peer assessment. AutoBench is distinct from Zapier's AutomationBench.

Weighted peer-assessment score

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GPQA Diamond

The highest-quality subset of Graduate-Level Google-Proof Q&A, designed to test expert-level scientific reasoning in biology, physics, and chemistry.

Accuracy

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Humanity's Last Exam

A 2,500-question expert-level benchmark spanning dozens of academic fields. Tool-assisted and no-tools results are separate protocols and must not be merged.

Accuracy

——
Arena preference scores
Arena (Text-to-Image)

Human preference score for generated images

1030 ±3
—

Benchmark sources

Reviewed evidence last updated 2026-08-09. Arena data last refreshed Oct 5, 2026.

Pricing, capabilities, and model facts

FLUX.2 Klein 4B and Nano Banana 2.1 model facts
FeatureFLUX.2 Klein 4BNano Banana 2.1
Context & model facts
DeveloperBlack Forest LabsGoogle
API providerBlack Forest LabsGoogle
Input context40,960 tokens65,536 tokens
Maximum output36,864 tokens58,982 tokens
Released——
Added to WritingmateJan 14, 2026Oct 6, 2026
LicenseNot availableNot available
Knowledge cutoff——
Capabilities
InputsText, ImageImage, Text
OutputsImageImage, Text
Provider endpoint accepts tool parametersNoYes
ReasoningNoYes
VisionYesYes
Image GenerationYesYes
Video GenerationNoNo
API performance
p95 latencyNot measuredNot measured
Output throughputNot measuredNot measured
Writingmate shows API performance only when both models have enough observations from the same measurement window, prompt profile, and provider. Third-party latency values are not copied into this table.

Data sources

  • Writingmate model catalog (pricing, limits, and availability)

Catalog data last updated Oct 6, 2026.

Why Pay for Multiple Subscriptions?

Comparing FLUX.2 Klein 4B from Black Forest Labs with Nano Banana 2.1 from Google? Instead of managing separate API keys and subscriptions, get both with Writingmate.

Subscription-plan access for FLUX.2 Klein 4B and Nano Banana 2.1
PlanPriceFLUX.2 Klein 4BNano Banana 2.1AI ImagesAI Video
Writingmate Pro
Most popular
$20/moIncludedIncludedNano Banana Pro, FLUX.2, DALL-E & moreVEO 3.1, Kling 3.0
Writingmate Ultimate
Power users
$60/moIncludedIncludedNano Banana Pro, FLUX.2, DALL-E & moreVEO 3.1, Kling 3.0
View Plans & Pricing

FLUX.2 Klein 4B vs Nano Banana 2.1 FAQ

Which is better, FLUX.2 Klein 4B or Nano Banana 2.1?

There are not enough shared, protocol-compatible benchmark results to declare a performance leader.

Which model is cheaper to use through an API?

A comparable blended token price is not available for both models. Check the API pricing rows for the values that are currently published.

Which model supports more context?

Comparable context-window data is not available for both models.

Can I switch between FLUX.2 Klein 4B and Nano Banana 2.1?

Yes. Use the model selector on this page to open any current Writingmate model comparison. You can also run the same prompt with both models in Writingmate.