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Comparison · 2 models · Updated Oct 4, 2026

Sakana Namazu vs Step 5 Preview

Step 5 Preview comes out ahead, 57 to 51 on our weighted score, and it is the cheaper option too.

  1. Sakana AI

    Sakana Namazu

    Released Aug 3, 2026

    51/100
    • ECI—
    • Price$0.95 / $4.00
    • Context262K
  2. Our pick

    StepFun

    Step 5 Preview

    Released Sep 16, 2026

    57/100
    • ECI—
    • Price$1.00 / $2.70
    • Context1M
  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Step 5 Preview is our pick

Step 5 Preview is the better all-round choice, scoring 57/100 against Sakana Namazu (51). It leads on price and context window. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

  • CapabilityNot enough dataNo independent benchmark covers every model here yet
  • Lowest priceStep 5 PreviewStep 5 Preview $1.43 · Sakana Namazu $1.71 per 1M tokens (3:1 blend)
  • Longest contextStep 5 PreviewStep 5 Preview 1,000,000 · Sakana Namazu 262,144 tokens
  • Widest inputsSame inputsSakana Namazu: Text, Images, PDFs · Step 5 Preview: Text, Images, Video
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightSakana NamazuStep 5 Preview
Price50%3943
Inputs & features30%8080
Context window20%3760
Overall100%51/10057/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Sakana Namazu vs Step 5 Preview specifications side by side
SpecificationSakana NamazuSakana AIStep 5 PreviewStepFun
Capability
Capabilities Index (ECI)——
ECI rank——
Price per million tokens
Input$0.95 (best)$1.00
Output$4.00$2.70 (best)
Cached input$0.15$0.05 (best)
Blended (3:1)$1.71$1.43 (best)
Long-context rateSame rateSame rate
Price sourceOfficial Sakana AI APIOfficial StepFun (Global) API
Limits
Context window262,144 tokens1,000,000 tokens (best)
Max output65,536 tokens1,000,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesNo
AudioNoNo
VideoNoYes
ReasoningYesYeslow · medium · high
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDsakana-namazustep-5-preview
API providers57 (best)
ReleasedAug 3, 2026Sep 16, 2026
Knowledge cutoff——
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • Sakana Namazu$17.50
  • Step 5 Preview$15.40
04 — Questions

Which should you choose?

Which is better: Sakana Namazu or Step 5 Preview?

Step 5 Preview is the better all-round choice, scoring 57/100 against Sakana Namazu (51). It leads on price and context window. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

Which is cheaper, Sakana Namazu or Step 5 Preview?

Step 5 Preview is cheaper at $1.00 input / $2.70 output per million tokens (official StepFun (Global) API price). Sakana Namazu costs $0.95 input / $4.00 output per million tokens (official Sakana AI API price). At a typical mix of three input tokens to one output token, that is $1.43 per million tokens for Step 5 Preview versus $1.71 for Sakana Namazu (1.2× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. Sakana Namazu has not been scored yet and Step 5 Preview has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for Sakana Namazu and Step 5 Preview yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Both support tool calling for agent workflows.

Which has the bigger context window?

Step 5 Preview has the largest context window at 1,000,000 tokens, against 262,144 for Sakana Namazu. Maximum output per response: Sakana Namazu up to 65,536, Step 5 Preview up to 1,000,000 tokens.

Which can read images, PDFs, audio or video?

Sakana Namazu accepts text, images and PDFs; Step 5 Preview accepts text, images and video. They handle the same number of input types.

Are any of these open source?

No. Sakana Namazu and Step 5 Preview are proprietary and only available through APIs and apps.

Which is newer?

Step 5 Preview is the newest, released Sep 16, 2026. Sakana Namazu came out Aug 3, 2026.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.