ZMIME
Comparison · 3 models · Updated Nov 2, 2026

Step 3.7 Flash vs LongCat-2.0 vs Perceptron Mk1

Step 3.7 Flash comes out ahead, 63 to 53 and 45 on our weighted score, and it is the cheaper option too.

  1. Our pick

    StepFun

    Step 3.7 Flash

    Released May 29, 2026

    63/100
    • ECI—
    • Price$0.20 / $1.15
    • Context256K
  2. Meituan (LongCat)

    LongCat-2.0

    Released Jun 30, 2026

    53/100
    • ECI—
    • Price$0.30 / $1.20
    • Context1M
  3. Perceptron

    Perceptron Mk1

    Released May 12, 2026

    45/100
    • ECI—
    • Price$0.15 / $1.50
    • Context33K
01 — Verdict

Step 3.7 Flash is our pick

Step 3.7 Flash is the better all-round choice, scoring 63/100 against LongCat-2.0 (53) and Perceptron Mk1 (45). It leads on price and inputs & features. LongCat-2.0 wins on context window. 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 priceStep 3.7 FlashStep 3.7 Flash $0.438 · Perceptron Mk1 $0.487 · LongCat-2.0 $0.525 per 1M tokens (3:1 blend)
  • Longest contextLongCat-2.0LongCat-2.0 1,000,000 · Step 3.7 Flash 256,000 · Perceptron Mk1 32,768 tokens
  • Widest inputsStep 3.7 Flash and Perceptron Mk1Step 3.7 Flash: Text, Images, Video · LongCat-2.0: Text · Perceptron Mk1: Text, Images, Video
  • Self-hostingStep 3.7 Flash and LongCat-2.0Publishes downloadable weights
How the score is built
MeasureWeightStep 3.7 FlashLongCat-2.0Perceptron Mk1
Price50%646062
Inputs & features30%803545
Context window20%36600
Overall100%63/10053/10045/100

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 3.7 Flash vs LongCat-2.0 vs Perceptron Mk1 specifications side by side
SpecificationStep 3.7 FlashStepFunLongCat-2.0Meituan (LongCat)Perceptron Mk1Perceptron
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.20$0.30$0.15 (best)
Output$1.15 (best)$1.20$1.50
Cached input$0.04$0.006 (best)—
Blended (3:1)$0.438 (best)$0.525$0.487
Long-context rateSame rateSame rateSame rate
Price sourceOfficial StepFun (Global) APIOfficial LongCat APIMedian of 3 providers
Limits
Context window256,000 tokens1,000,000 tokens (best)32,768 tokens
Max output256,000 tokens (best)131,072 tokens8,192 tokens
Inputs and features
TextYesYesYes
ImagesYesNoYes
PDFsNoNoNo
AudioNoNoNo
VideoYesNoYes
ReasoningYeslow · medium · highYesYes
Tool callingYesYesNo
Structured outputYesNoNo
Availability
WeightsOpenOpenProprietary
API model IDstep-3.7-flashLongCat-2.0—
API providers19 (best)73
ReleasedMay 29, 2026Jun 30, 2026May 12, 2026
Knowledge cutoffMar 1, 2026——
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 3.7 Flash$4.30
  • LongCat-2.0$5.40
  • Perceptron Mk1$4.50
04 — Questions

Which should you choose?

Which is better: Step 3.7 Flash, LongCat-2.0 or Perceptron Mk1?

Step 3.7 Flash is the better all-round choice, scoring 63/100 against LongCat-2.0 (53) and Perceptron Mk1 (45). It leads on price and inputs & features. LongCat-2.0 wins on context window. 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 3.7 Flash, LongCat-2.0 or Perceptron Mk1?

Step 3.7 Flash is cheaper at $0.20 input / $1.15 output per million tokens (official StepFun (Global) API price). Perceptron Mk1 costs $0.15 input / $1.50 output per million tokens (median across 3 API providers); LongCat-2.0 costs $0.30 input / $1.20 output per million tokens (official LongCat API price). At a typical mix of three input tokens to one output token, that is $0.438 per million tokens for Step 3.7 Flash versus $0.487 for Perceptron Mk1 (1.1× as much) and $0.525 for LongCat-2.0 (1.2× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. Step 3.7 Flash has not been scored yet, LongCat-2.0 has not been scored yet and Perceptron Mk1 has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for Step 3.7 Flash, LongCat-2.0 and Perceptron Mk1 yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Note that Perceptron Mk1 does not support tool calling, which most coding agents need.

Which has the bigger context window?

LongCat-2.0 has the largest context window at 1,000,000 tokens, against 256,000 for Step 3.7 Flash and 32,768 for Perceptron Mk1. Maximum output per response: Step 3.7 Flash up to 256,000, LongCat-2.0 up to 131,072, Perceptron Mk1 up to 8,192 tokens.

Which can read images, PDFs, audio or video?

Step 3.7 Flash accepts text, images and video; LongCat-2.0 accepts text; Perceptron Mk1 accepts text, images and video. Step 3.7 Flash handles the widest range of inputs.

Are any of these open source?

Step 3.7 Flash and LongCat-2.0 publishes its weights and can be self-hosted; Perceptron Mk1 is proprietary.

Which is newer?

LongCat-2.0 is the newest, released Jun 30, 2026. Step 3.7 Flash came out May 29, 2026; Perceptron Mk1 came out May 12, 2026. Knowledge cutoff: Step 3.7 Flash Mar 1, 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 Nov 2, 2026.