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Comparison · 3 models · Updated Oct 4, 2026

Hy4 preview vs Step 5 Preview vs LongCat-2.5-Preview

Step 5 Preview comes out ahead, 57 to 52 and 45 on our weighted score, though Hy4 preview is 12% cheaper per token.

  1. Tencent

    Hy4 preview

    Released Aug 28, 2026

    45/100
    • ECI—
    • Price$0.834 / $2.50
    • Context1.02M
  2. Our pick

    StepFun

    Step 5 Preview

    Released Sep 16, 2026

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

    LongCat-2.5-Preview

    Released Sep 25, 2026

    52/100
    • ECI—
    • Price$0.75 / $2.95
    • 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 Hy4 preview (45). It leads on inputs & features. 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 priceHy4 previewHy4 preview $1.25 · LongCat-2.5-Preview $1.30 · Step 5 Preview $1.43 per 1M tokens (3:1 blend)
  • Longest contextHy4 previewHy4 preview 1,024,000 · Step 5 Preview 1,000,000 · LongCat-2.5-Preview 1,000,000 tokens
  • Widest inputsStep 5 PreviewHy4 preview: Text · Step 5 Preview: Text, Images, Video · LongCat-2.5-Preview: Text, Images
  • Self-hostingHy4 previewPublishes downloadable weights
How the score is built
MeasureWeightHy4 previewStep 5 PreviewLongCat-2.5-Preview
Price50%454344
Inputs & features30%358060
Context window20%606060
Overall100%45/10057/10052/100

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.

Hy4 preview vs Step 5 Preview vs LongCat-2.5-Preview specifications side by side
SpecificationHy4 previewTencentStep 5 PreviewStepFunLongCat-2.5-PreviewMeituan (LongCat)
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.834$1.00$0.75 (best)
Output$2.50 (best)$2.70$2.95
Cached input$0.042 (best)$0.05—
Blended (3:1)$1.25 (best)$1.43$1.30
Long-context rateSame rateSame rateSame rate
Price sourceOfficial Tencent TokenHub APIOfficial StepFun (Global) APIMedian of 1 providers
Limits
Context window1,024,000 tokens (best)1,000,000 tokens1,000,000 tokens
Max output64,000 tokens1,000,000 tokens (best)131,072 tokens
Inputs and features
TextYesYesYes
ImagesNoYesYes
PDFsNoNoNo
AudioNoNoNo
VideoNoYesNo
ReasoningYeshighYeslow · medium · highYes
Tool callingYesYesYes
Structured outputNoYesNo
Availability
WeightsOpenProprietaryProprietary
API model IDhy4-previewstep-5-preview—
API providers13 (best)72
ReleasedAug 28, 2026Sep 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.

  • Hy4 preview$13.34
  • Step 5 Preview$15.40
  • LongCat-2.5-Preview$13.40
04 — Questions

Which should you choose?

Which is better: Hy4 preview, 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) and Hy4 preview (45). It leads on inputs & features. 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, Hy4 preview, Step 5 Preview or LongCat-2.5-Preview?

Hy4 preview is cheaper at $0.834 input / $2.50 output per million tokens (official Tencent TokenHub API price). LongCat-2.5-Preview costs $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 $1.25 per million tokens for Hy4 preview versus $1.30 for LongCat-2.5-Preview (1× as much) and $1.43 for Step 5 Preview (1.1× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. Hy4 preview has not been scored 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 Hy4 preview, 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. All three support tool calling for agent workflows.

Which has the bigger context window?

Hy4 preview has the largest context window at 1,024,000 tokens, against 1,000,000 for Step 5 Preview and 1,000,000 for LongCat-2.5-Preview. Maximum output per response: Hy4 preview up to 64,000, 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?

Hy4 preview accepts text; 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?

Hy4 preview publishes its weights and can be self-hosted; Step 5 Preview and LongCat-2.5-Preview is proprietary.

Which is newer?

LongCat-2.5-Preview is the newest, released Sep 25, 2026. Step 5 Preview came out Sep 16, 2026; Hy4 preview came out Aug 28, 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.