ZMIME
Comparison · 3 models · Updated Oct 4, 2026

Trinity Large Thinking vs Step 3.5 Flash 2603 vs Mercury Edit 2

Step 3.5 Flash 2603 comes out ahead, 62 to 55 and 35 on our weighted score, and it is the cheaper option too.

  1. Arcee AI

    Trinity Large Thinking

    Released Apr 1, 2026Beta

    55/100
    • ECI—
    • Price$0.25 / $0.80
    • Context524K
  2. Our pick

    StepFun

    Step 3.5 Flash 2603

    Released Apr 2, 2026

    62/100
    • ECI—
    • Price$0.10 / $0.30
    • Context256K
  3. Inception

    Mercury Edit 2

    Released Mar 30, 2026

    35/100
    • ECI—
    • Price$0.25 / $0.75
    • Context32K
01 — Verdict

Step 3.5 Flash 2603 is our pick

Step 3.5 Flash 2603 is the better all-round choice, scoring 62/100 against Trinity Large Thinking (55) and Mercury Edit 2 (35). It leads on price. Trinity Large Thinking 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 3.5 Flash 2603Step 3.5 Flash 2603 $0.15 · Mercury Edit 2 $0.375 · Trinity Large Thinking $0.388 per 1M tokens (3:1 blend)
  • Longest contextTrinity Large ThinkingTrinity Large Thinking 524,288 · Step 3.5 Flash 2603 256,000 · Mercury Edit 2 32,000 tokens
  • Widest inputsSame inputsTrinity Large Thinking: Text · Step 3.5 Flash 2603: Text · Mercury Edit 2: Text
  • Self-hostingTrinity Large Thinking and Step 3.5 Flash 2603Publishes downloadable weights (OpenMDW-1.1)
How the score is built
MeasureWeightTrinity Large ThinkingStep 3.5 Flash 2603Mercury Edit 2
Price50%698970
Inputs & features30%35350
Context window20%49360
Overall100%55/10062/10035/100

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.

Trinity Large Thinking vs Step 3.5 Flash 2603 vs Mercury Edit 2 specifications side by side
SpecificationTrinity Large ThinkingArcee AIStep 3.5 Flash 2603StepFunMercury Edit 2Inception
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.25$0.10 (best)$0.25
Output$0.80$0.30 (best)$0.75
Cached input$0.06$0.02 (best)$0.025
Blended (3:1)$0.388$0.15 (best)$0.375
Long-context rateSame rateSame rateSame rate
Price sourceOfficial Arcee APIOfficial StepFun (Global) APIOfficial Inception API
Limits
Context window524,288 tokens (best)256,000 tokens32,000 tokens
Max output262,144 tokens (best)256,000 tokens8,192 tokens
Inputs and features
TextYesYesYes
ImagesNoNoNo
PDFsNoNoNo
AudioNoNoNo
VideoNoNoNo
ReasoningYesYeslow · highNo
Tool callingYesYesNo
Structured outputNoNoNo
Availability
WeightsOpenOpenMDW-1.1OpenProprietary
API model IDtrinity-large-thinkingstep-3.5-flash-2603mercury-edit-2
API providers6 (best)31
ReleasedApr 1, 2026Apr 2, 2026Mar 30, 2026
Knowledge cutoff—Jan 2025—
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.

  • Trinity Large Thinking$4.10
  • Step 3.5 Flash 2603$1.60
  • Mercury Edit 2$4.00
04 — Questions

Which should you choose?

Which is better: Trinity Large Thinking, Step 3.5 Flash 2603 or Mercury Edit 2?

Step 3.5 Flash 2603 is the better all-round choice, scoring 62/100 against Trinity Large Thinking (55) and Mercury Edit 2 (35). It leads on price. Trinity Large Thinking 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, Trinity Large Thinking, Step 3.5 Flash 2603 or Mercury Edit 2?

Step 3.5 Flash 2603 is cheaper at $0.10 input / $0.30 output per million tokens (official StepFun (Global) API price). Mercury Edit 2 costs $0.25 input / $0.75 output per million tokens (official Inception API price); Trinity Large Thinking costs $0.25 input / $0.80 output per million tokens (official Arcee API price). At a typical mix of three input tokens to one output token, that is $0.15 per million tokens for Step 3.5 Flash 2603 versus $0.375 for Mercury Edit 2 (2.5× as much) and $0.388 for Trinity Large Thinking (2.6× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. Trinity Large Thinking has not been scored yet, Step 3.5 Flash 2603 has not been scored yet and Mercury Edit 2 has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for Trinity Large Thinking, Step 3.5 Flash 2603 and Mercury Edit 2 yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Note that Mercury Edit 2 does not support tool calling, which most coding agents need.

Which has the bigger context window?

Trinity Large Thinking has the largest context window at 524,288 tokens, against 256,000 for Step 3.5 Flash 2603 and 32,000 for Mercury Edit 2. Maximum output per response: Trinity Large Thinking up to 262,144, Step 3.5 Flash 2603 up to 256,000, Mercury Edit 2 up to 8,192 tokens.

Which can read images, PDFs, audio or video?

Trinity Large Thinking accepts text; Step 3.5 Flash 2603 accepts text; Mercury Edit 2 accepts text. They handle the same number of input types.

Are any of these open source?

Trinity Large Thinking and Step 3.5 Flash 2603 publishes its weights (OpenMDW-1.1) and can be self-hosted; Mercury Edit 2 is proprietary.

Which is newer?

Step 3.5 Flash 2603 is the newest, released Apr 2, 2026. Trinity Large Thinking came out Apr 1, 2026; Mercury Edit 2 came out Mar 30, 2026. Knowledge cutoff: Step 3.5 Flash 2603 Jan 2025.

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.