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Model Comparison

Nano Banana (Gemini 2.5 Flash Image) vs Fugu Ultra v2Which Is Better in 2026?

Nano Banana (Gemini 2.5 Flash Image) vs Fugu Ultra v2: which should you choose in 2026?

Nano Banana (Gemini 2.5 Flash Image) (by Google) and Fugu Ultra v2 (by Sakana AI) 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 Nano Banana (Gemini 2.5 Flash Image) if…

  • you need image generation

Choose Fugu Ultra v2 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.

Nano Banana (Gemini 2.5 Flash Image) and Fugu Ultra v2 benchmark results
BenchmarkNano Banana (Gemini 2.5 Flash Image)Fugu Ultra v2
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

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

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

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

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

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

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

LMArena Text-to-Image

Human preference rankings for image generation models based on blind comparisons

Elo Score

Benchmark sources

Reviewed evidence last updated 2025-12-28.

Pricing, capabilities, and model facts

Nano Banana (Gemini 2.5 Flash Image) and Fugu Ultra v2 model facts
FeatureNano Banana (Gemini 2.5 Flash Image)Fugu Ultra v2
Context & model facts
DeveloperGoogleSakana AI
API providerGoogleSakana
Input context32,768 tokens1,000,000 tokens
Maximum output8,192 tokens128,000 tokens
Released
Added to WritingmateOct 7, 2025Sep 11, 2026
LicenseNot availableNot available
Knowledge cutoff2025-01-312026-08-28
Capabilities
InputsImage, TextText, Image, File
OutputsImage, TextText
Provider endpoint accepts tool parametersNoYes
ReasoningNoYes
VisionYesYes
Image GenerationYesNo
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 Sep 11, 2026.

Why Pay for Multiple Subscriptions?

Comparing Nano Banana (Gemini 2.5 Flash Image) from Google with Fugu Ultra v2 from Sakana AI? Instead of managing separate API keys and subscriptions, get both with Writingmate.

Subscription-plan access for Nano Banana (Gemini 2.5 Flash Image) and Fugu Ultra v2
PlanPriceNano Banana (Gemini 2.5 Flash Image)Fugu Ultra v2AI ImagesAI Video
Writingmate Pro
Most popular
$20/moIncludedUltimate requiredNano Banana Pro, FLUX.2, DALL-E & moreSora 2, VEO 3.1
Writingmate Ultimate
Power users
$60/moIncludedIncludedNano Banana Pro, FLUX.2, DALL-E & moreSora 2, VEO 3.1

Nano Banana (Gemini 2.5 Flash Image) vs Fugu Ultra v2 FAQ

Which is better, Nano Banana (Gemini 2.5 Flash Image) or Fugu Ultra v2?

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 Nano Banana (Gemini 2.5 Flash Image) and Fugu Ultra v2?

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.