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Comparison · 2 models · Updated Oct 4, 2026

Step 5 Preview vs Sakana Namazu

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

  1. Our pick

    StepFun

    Step 5 Preview

    Released Sep 16, 2026

    57/100
    • ECI—
    • Price$1.00 / $2.70
    • Context1M
    Full specs Remove Step 5 Preview

  2. Sakana AI

    Sakana Namazu

    Released Aug 3, 2026

    51/100
    • ECI—
    • Price$0.95 / $4.00
    • Context262K
    Full specs Remove Sakana Namazu

  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 inputsStep 5 Preview: Text, Images, Video · Sakana Namazu: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightStep 5 PreviewSakana Namazu
Price50%4339
Inputs & features30%8080
Context window20%6037
Overall100%57/10051/100

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.

Step 5 Preview vs Sakana Namazu specifications side by side
SpecificationStep 5 PreviewStepFunSakana NamazuSakana AI
Capability
Capabilities Index (ECI)——
ECI rank——
Price per million tokens
Input$1.00$0.95 (best)
Output$2.70 (best)$4.00
Cached input$0.05 (best)$0.15
Blended (3:1)$1.43 (best)$1.71
Long-context rateSame rateSame rate
Price sourceOfficial StepFun (Global) APIOfficial Sakana AI API
Limits
Context window1,000,000 tokens (best)262,144 tokens
Max output1,000,000 tokens (best)65,536 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoYes
AudioNoNo
VideoYesNo
ReasoningYeslow · medium · highYes
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDstep-5-previewsakana-namazu
API providers7 (best)5
ReleasedSep 16, 2026Aug 3, 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.

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

Which should you choose?

Which is better: Step 5 Preview or Sakana Namazu?

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, Step 5 Preview or Sakana Namazu?

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. Step 5 Preview has not been scored yet and Sakana Namazu has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for Step 5 Preview and Sakana Namazu 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: Step 5 Preview up to 1,000,000, Sakana Namazu up to 65,536 tokens.

Which can read images, PDFs, audio or video?

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

Are any of these open source?

No. Step 5 Preview and Sakana Namazu 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.

05 — Keep comparing

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