ZMIME
Comparison · 3 models · Updated Nov 2, 2026

Perceptron Mk1 vs Step 3.7 Flash vs CoBuddy

Step 3.7 Flash comes out ahead, 63 to 46 and 45 on our weighted score, and it is the cheaper option too.

  1. Perceptron

    Perceptron Mk1

    Released May 12, 2026

    45/100
    • ECI—
    • Price$0.15 / $1.50
    • Context33K
  2. Our pick

    StepFun

    Step 3.7 Flash

    Released May 29, 2026

    63/100
    • ECI—
    • Price$0.20 / $1.15
    • Context256K
  3. Baidu

    CoBuddy

    Released May 6, 2026

    46/100
    • ECI—
    • Price$0.28 / $1.13
    • Context131K
01 — Verdict

Step 3.7 Flash is our pick

Step 3.7 Flash is the better all-round choice, scoring 63/100 against CoBuddy (46) and Perceptron Mk1 (45). It leads on price, inputs & features and 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 · CoBuddy $0.492 per 1M tokens (3:1 blend)
  • Longest contextStep 3.7 FlashStep 3.7 Flash 256,000 · CoBuddy 131,072 · Perceptron Mk1 32,768 tokens
  • Widest inputsPerceptron Mk1 and Step 3.7 FlashPerceptron Mk1: Text, Images, Video · Step 3.7 Flash: Text, Images, Video · CoBuddy: Text
  • Self-hostingStep 3.7 FlashPublishes downloadable weights
How the score is built
MeasureWeightPerceptron Mk1Step 3.7 FlashCoBuddy
Price50%626462
Inputs & features30%458035
Context window20%03625
Overall100%45/10063/10046/100

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.

Perceptron Mk1 vs Step 3.7 Flash vs CoBuddy specifications side by side
SpecificationPerceptron Mk1PerceptronStep 3.7 FlashStepFunCoBuddyBaidu
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.15 (best)$0.20$0.28
Output$1.50$1.15$1.13 (best)
Cached input—$0.04—
Blended (3:1)$0.487$0.438 (best)$0.492
Long-context rateSame rateSame rateSame rate
Price sourceMedian of 3 providersOfficial StepFun (Global) APIMedian of 1 providers
Limits
Context window32,768 tokens256,000 tokens (best)131,072 tokens
Max output8,192 tokens256,000 tokens (best)65,536 tokens
Inputs and features
TextYesYesYes
ImagesYesYesNo
PDFsNoNoNo
AudioNoNoNo
VideoYesYesNo
ReasoningYesYeslow · medium · highYes
Tool callingNoYesYes
Structured outputNoYesNo
Availability
WeightsProprietaryOpenProprietary
API model ID—step-3.7-flash—
API providers319 (best)1
ReleasedMay 12, 2026May 29, 2026May 6, 2026
Knowledge cutoff—Mar 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.

  • Perceptron Mk1$4.50
  • Step 3.7 Flash$4.30
  • CoBuddy$5.06
04 — Questions

Which should you choose?

Which is better: Perceptron Mk1, Step 3.7 Flash or CoBuddy?

Step 3.7 Flash is the better all-round choice, scoring 63/100 against CoBuddy (46) and Perceptron Mk1 (45). It leads on price, inputs & features and 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, Perceptron Mk1, Step 3.7 Flash or CoBuddy?

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); CoBuddy costs $0.28 input / $1.13 output per million tokens (median across 1 API provider). 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 $0.492 for CoBuddy (1.1× as much).

Which scores higher on benchmarks?

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

Which is better for coding?

There are no published SWE-bench Verified results for Perceptron Mk1, Step 3.7 Flash and CoBuddy 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?

Step 3.7 Flash has the largest context window at 256,000 tokens, against 131,072 for CoBuddy and 32,768 for Perceptron Mk1. Maximum output per response: Perceptron Mk1 up to 8,192, Step 3.7 Flash up to 256,000, CoBuddy up to 65,536 tokens.

Which can read images, PDFs, audio or video?

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

Are any of these open source?

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

Which is newer?

Step 3.7 Flash is the newest, released May 29, 2026. Perceptron Mk1 came out May 12, 2026; CoBuddy came out May 6, 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.