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Comparison · 3 models · Updated Oct 4, 2026

LongCat-2.5-Preview vs Qwen3.5 122B-A10B vs Step 5 Preview

Too close to call on our weighted score (Qwen3.5 122B-A10B 58, Step 5 Preview 57, LongCat-2.5-Preview 52). The right pick depends on what you value most.

  1. Meituan (LongCat)

    LongCat-2.5-Preview

    Released Sep 25, 2026

    52/100
    • ECI—
    • Price$0.75 / $2.95
    • Context1M
  2. Alibaba (Qwen)

    Qwen3.5 122B-A10B

    Released Feb 23, 2026

    58/100
    • ECI—
    • Price$0.40 / $3.20
    • Context262K
  3. StepFun

    Step 5 Preview

    Released Sep 16, 2026

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

Too close to call

It is close. Our weighted score puts them within 1 points (Qwen3.5 122B-A10B 58/100, Step 5 Preview 57/100, LongCat-2.5-Preview 52/100), so choose by what matters most for your work: Qwen3.5 122B-A10B 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 priceQwen3.5 122B-A10BQwen3.5 122B-A10B $1.10 · LongCat-2.5-Preview $1.30 · Step 5 Preview $1.43 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 · Qwen3.5 122B-A10B 262,144 tokens
  • Widest inputsQwen3.5 122B-A10BLongCat-2.5-Preview: Text, Images · Qwen3.5 122B-A10B: Text, Images, Audio, Video · Step 5 Preview: Text, Images, Video
  • Self-hostingQwen3.5 122B-A10BPublishes downloadable weights
How the score is built
MeasureWeightLongCat-2.5-PreviewQwen3.5 122B-A10BStep 5 Preview
Price50%444843
Inputs & features30%609080
Context window20%603760
Overall100%52/10058/10057/100

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 Qwen3.5 122B-A10B vs Step 5 Preview specifications side by side
SpecificationLongCat-2.5-PreviewMeituan (LongCat)Qwen3.5 122B-A10BAlibaba (Qwen)Step 5 PreviewStepFun
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.75$0.40 (best)$1.00
Output$2.95$3.20$2.70 (best)
Cached input——$0.05
Blended (3:1)$1.30$1.10 (best)$1.43
Long-context rateSame rateSame rateSame rate
Price sourceMedian of 1 providersOfficial Alibaba 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
PDFsNoNoNo
AudioNoYesNo
VideoNoYesYes
ReasoningYesYesYeslow · medium · high
Tool callingYesYesYes
Structured outputNoYesYes
Availability
WeightsProprietaryOpenProprietary
API model ID—qwen3.5-122b-a10bstep-5-preview
API providers219 (best)7
ReleasedSep 25, 2026Feb 23, 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
  • Qwen3.5 122B-A10B$10.40
  • Step 5 Preview$15.40
04 — Questions

Which should you choose?

Which is better: LongCat-2.5-Preview, Qwen3.5 122B-A10B or Step 5 Preview?

It is close. Our weighted score puts them within 1 points (Qwen3.5 122B-A10B 58/100, Step 5 Preview 57/100, LongCat-2.5-Preview 52/100), so choose by what matters most for your work: Qwen3.5 122B-A10B 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, Qwen3.5 122B-A10B or Step 5 Preview?

Qwen3.5 122B-A10B is cheaper at $0.40 input / $3.20 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 $1.10 per million tokens for Qwen3.5 122B-A10B versus $1.30 for LongCat-2.5-Preview (1.2× as much) and $1.43 for Step 5 Preview (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, Qwen3.5 122B-A10B 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, Qwen3.5 122B-A10B 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 Qwen3.5 122B-A10B. Maximum output per response: LongCat-2.5-Preview up to 131,072, Qwen3.5 122B-A10B 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; Qwen3.5 122B-A10B accepts text, images, audio and video; Step 5 Preview accepts text, images and video. Qwen3.5 122B-A10B handles the widest range of inputs.

Are any of these open source?

Qwen3.5 122B-A10B publishes its weights and can be self-hosted; LongCat-2.5-Preview and Step 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; Qwen3.5 122B-A10B came out Feb 23, 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.