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Comparison · 2 models · Updated Oct 4, 2026

Step 5 Preview vs LongCat-2.5-Preview

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

  1. Our pick

    StepFun

    Step 5 Preview

    Released Sep 16, 2026

    57/100
    • ECI—
    • Price$1.00 / $2.70
    • Context1M
  2. Meituan (LongCat)

    LongCat-2.5-Preview

    Released Sep 25, 2026

    52/100
    • ECI—
    • Price$0.75 / $2.95
    • Context1M
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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). It leads on inputs & features. 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 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameStep 5 Preview 1,000,000 · LongCat-2.5-Preview 1,000,000 tokens
  • Widest inputsStep 5 PreviewStep 5 Preview: Text, Images, Video · LongCat-2.5-Preview: Text, Images
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightStep 5 PreviewLongCat-2.5-Preview
Price50%4344
Inputs & features30%8060
Context window20%6060
Overall100%57/10052/100

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 LongCat-2.5-Preview specifications side by side
SpecificationStep 5 PreviewStepFunLongCat-2.5-PreviewMeituan (LongCat)
Capability
Capabilities Index (ECI)——
ECI rank——
Price per million tokens
Input$1.00$0.75 (best)
Output$2.70 (best)$2.95
Cached input$0.05—
Blended (3:1)$1.43$1.30 (best)
Long-context rateSame rateSame rate
Price sourceOfficial StepFun (Global) APIMedian of 1 providers
Limits
Context window1,000,000 tokens1,000,000 tokens
Max output1,000,000 tokens (best)131,072 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoNo
AudioNoNo
VideoYesNo
ReasoningYeslow · medium · highYes
Tool callingYesYes
Structured outputYesNo
Availability
WeightsProprietaryProprietary
API model IDstep-5-preview—
API providers7 (best)2
ReleasedSep 16, 2026Sep 25, 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
  • LongCat-2.5-Preview$13.40
04 — Questions

Which should you choose?

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

Step 5 Preview is the better all-round choice, scoring 57/100 against LongCat-2.5-Preview (52). It leads on inputs & features. 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, Step 5 Preview or LongCat-2.5-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). 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).

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. Step 5 Preview has not been scored yet and LongCat-2.5-Preview has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for Step 5 Preview and LongCat-2.5-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 and LongCat-2.5-Preview share the same 1,000,000-token context window. Maximum output per response: Step 5 Preview up to 1,000,000, LongCat-2.5-Preview up to 131,072 tokens.

Which can read images, PDFs, audio or video?

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

Are any of these open source?

No. Step 5 Preview and LongCat-2.5-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.

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.