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Comparison · 3 models · Updated Oct 4, 2026

LongCat-2.5-Preview vs Sakana Namazu vs Step 5 Preview

Step 5 Preview comes out ahead, 57 to 52 and 51 on our weighted score, though LongCat-2.5-Preview is 9% cheaper per token.

  1. Meituan (LongCat)

    LongCat-2.5-Preview

    Released Sep 25, 2026

    52/100
    • ECI—
    • Price$0.75 / $2.95
    • Context1M
  2. Sakana AI

    Sakana Namazu

    Released Aug 3, 2026

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

    StepFun

    Step 5 Preview

    Released Sep 16, 2026

    57/100
    • ECI—
    • Price$1.00 / $2.70
    • Context1M
01 — Verdict

Step 5 Preview is our pick

Step 5 Preview is the better all-round choice, scoring 57/100 against LongCat-2.5-Preview (52) and Sakana Namazu (51). LongCat-2.5-Preview wins on price. 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 priceLongCat-2.5-PreviewLongCat-2.5-Preview $1.30 · Step 5 Preview $1.43 · Sakana Namazu $1.71 per 1M tokens (3:1 blend)
  • Longest contextLongCat-2.5-Preview and Step 5 PreviewLongCat-2.5-Preview 1,000,000 · Step 5 Preview 1,000,000 · Sakana Namazu 262,144 tokens
  • Widest inputsSakana Namazu and Step 5 PreviewLongCat-2.5-Preview: Text, Images · Sakana Namazu: Text, Images, PDFs · Step 5 Preview: Text, Images, Video
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightLongCat-2.5-PreviewSakana NamazuStep 5 Preview
Price50%443943
Inputs & features30%608080
Context window20%603760
Overall100%52/10051/10057/100

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.

LongCat-2.5-Preview vs Sakana Namazu vs Step 5 Preview specifications side by side
SpecificationLongCat-2.5-PreviewMeituan (LongCat)Sakana NamazuSakana AIStep 5 PreviewStepFun
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.75 (best)$0.95$1.00
Output$2.95$4.00$2.70 (best)
Cached input—$0.15$0.05 (best)
Blended (3:1)$1.30 (best)$1.71$1.43
Long-context rateSame rateSame rateSame rate
Price sourceMedian of 1 providersOfficial Sakana AI APIOfficial StepFun (Global) API
Limits
Context window1,000,000 tokens (best)262,144 tokens1,000,000 tokens (best)
Max output131,072 tokens65,536 tokens1,000,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsNoYesNo
AudioNoNoNo
VideoNoNoYes
ReasoningYesYesYeslow · medium · high
Tool callingYesYesYes
Structured outputNoYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model ID—sakana-namazustep-5-preview
API providers257 (best)
ReleasedSep 25, 2026Aug 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.

  • LongCat-2.5-Preview$13.40
  • Sakana Namazu$17.50
  • Step 5 Preview$15.40
04 — Questions

Which should you choose?

Which is better: LongCat-2.5-Preview, Sakana Namazu or Step 5 Preview?

Step 5 Preview is the better all-round choice, scoring 57/100 against LongCat-2.5-Preview (52) and Sakana Namazu (51). LongCat-2.5-Preview wins on price. 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, LongCat-2.5-Preview, Sakana Namazu or Step 5 Preview?

LongCat-2.5-Preview is cheaper at $0.75 input / $2.95 output per million tokens (median across 1 API provider). Step 5 Preview costs $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 $1.30 per million tokens for LongCat-2.5-Preview versus $1.43 for Step 5 Preview (1.1× as much) and $1.71 for Sakana Namazu (1.3× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. LongCat-2.5-Preview has not been scored 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 LongCat-2.5-Preview, 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. All three support tool calling for agent workflows.

Which has the bigger context window?

LongCat-2.5-Preview and Step 5 Preview have the largest context windows (1,000,000 and 1,000,000 tokens), against 262,144 for Sakana Namazu. Maximum output per response: LongCat-2.5-Preview up to 131,072, Sakana Namazu up to 65,536, Step 5 Preview up to 1,000,000 tokens.

Which can read images, PDFs, audio or video?

LongCat-2.5-Preview accepts text and images; Sakana Namazu accepts text, images and PDFs; Step 5 Preview accepts text, images and video. Sakana Namazu handles the widest range of inputs.

Are any of these open source?

No. LongCat-2.5-Preview, Sakana Namazu and Step 5 Preview are proprietary and only available through APIs and apps.

Which is newer?

LongCat-2.5-Preview is the newest, released Sep 25, 2026. Step 5 Preview came out 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.