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Comparison · 3 models · Updated Oct 4, 2026

LongCat-2.5-Preview vs Qwen3.8 Flash vs Step 5 Preview

Qwen3.8 Flash comes out ahead, 76 to 57 and 52 on our weighted score, and it is the cheaper option too.

  1. Meituan (LongCat)

    LongCat-2.5-Preview

    Released Sep 25, 2026

    52/100
    • ECI—
    • Price$0.75 / $2.95
    • Context1M
  2. Our pick

    Alibaba (Qwen)

    Qwen3.8 Flash

    Released Aug 26, 2026

    76/100
    • ECI—
    • Price$0.15 / $0.47
    • Context1M
  3. StepFun

    Step 5 Preview

    Released Sep 16, 2026

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

Qwen3.8 Flash is our pick

Qwen3.8 Flash is the better all-round choice, scoring 76/100 against Step 5 Preview (57) and LongCat-2.5-Preview (52). It leads 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 priceQwen3.8 FlashQwen3.8 Flash $0.23 · LongCat-2.5-Preview $1.30 · Step 5 Preview $1.43 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameLongCat-2.5-Preview 1,000,000 · Qwen3.8 Flash 1,000,000 · Step 5 Preview 1,000,000 tokens
  • Widest inputsQwen3.8 Flash and Step 5 PreviewLongCat-2.5-Preview: Text, Images · Qwen3.8 Flash: Text, Images, Video · Step 5 Preview: Text, Images, Video
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightLongCat-2.5-PreviewQwen3.8 FlashStep 5 Preview
Price50%448043
Inputs & features30%608080
Context window20%606060
Overall100%52/10076/10057/100

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 Qwen3.8 Flash vs Step 5 Preview specifications side by side
SpecificationLongCat-2.5-PreviewMeituan (LongCat)Qwen3.8 FlashAlibaba (Qwen)Step 5 PreviewStepFun
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.75$0.15 (best)$1.00
Output$2.95$0.47 (best)$2.70
Cached input—$0.016 (best)$0.05
Blended (3:1)$1.30$0.23 (best)$1.43
Long-context rateSame rateSame rateSame rate
Price sourceMedian of 1 providersOfficial Alibaba APIOfficial StepFun (Global) API
Limits
Context window1,000,000 tokens1,000,000 tokens1,000,000 tokens
Max output131,072 tokens131,072 tokens1,000,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsNoNoNo
AudioNoNoNo
VideoNoYesYes
ReasoningYesYeslow · medium · xhighYeslow · medium · high
Tool callingYesYesYes
Structured outputNoYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model ID—qwen3.8-flashstep-5-preview
API providers223 (best)7
ReleasedSep 25, 2026Aug 26, 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
  • Qwen3.8 Flash$2.44
  • Step 5 Preview$15.40
04 — Questions

Which should you choose?

Which is better: LongCat-2.5-Preview, Qwen3.8 Flash or Step 5 Preview?

Qwen3.8 Flash is the better all-round choice, scoring 76/100 against Step 5 Preview (57) and LongCat-2.5-Preview (52). It leads 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, Qwen3.8 Flash or Step 5 Preview?

Qwen3.8 Flash is cheaper at $0.15 input / $0.47 output per million tokens (official Alibaba 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 $0.23 per million tokens for Qwen3.8 Flash versus $1.30 for LongCat-2.5-Preview (5.7× as much) and $1.43 for Step 5 Preview (6.2× 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, Qwen3.8 Flash 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, Qwen3.8 Flash 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, Qwen3.8 Flash and Step 5 Preview share the same 1,000,000-token context window. Maximum output per response: LongCat-2.5-Preview up to 131,072, Qwen3.8 Flash up to 131,072, 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; Qwen3.8 Flash accepts text, images and video; Step 5 Preview accepts text, images and video. Qwen3.8 Flash handles the widest range of inputs.

Are any of these open source?

No. LongCat-2.5-Preview, Qwen3.8 Flash 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; Qwen3.8 Flash came out Aug 26, 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.