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Comparison · 3 models · Updated Oct 4, 2026

Step 2 (16K) vs Sonar Reasoning Pro vs Qwen-MT Plus

Sonar Reasoning Pro comes out ahead, 27 to 12 and 11 on our weighted score, and it is the cheaper option too.

  1. StepFun

    Step 2 (16K)

    Released Jan 1, 2025

    11/100
    • ECI—
    • Price$5.21 / $16.44
    • Context16K
  2. Our pick

    Perplexity

    Sonar Reasoning Pro

    Released Jan 1, 2024

    27/100
    • ECI—
    • Price$2.00 / $8.00
    • Context128K
  3. Alibaba (Qwen)

    Qwen-MT Plus

    Released Jan 2025

    12/100
    • ECI—
    • Price$2.46 / $7.37
    • Context16K
01 — Verdict

Sonar Reasoning Pro is our pick

Sonar Reasoning Pro is the better all-round choice, scoring 27/100 against Qwen-MT Plus (12) and Step 2 (16K) (11). It leads on 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 priceSonar Reasoning ProSonar Reasoning Pro $3.50 · Qwen-MT Plus $3.69 · Step 2 (16K) $8.02 per 1M tokens (3:1 blend)
  • Longest contextSonar Reasoning ProSonar Reasoning Pro 128,000 · Step 2 (16K) 16,384 · Qwen-MT Plus 16,384 tokens
  • Widest inputsSonar Reasoning ProStep 2 (16K): Text · Sonar Reasoning Pro: Text, Images · Qwen-MT Plus: Text
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightStep 2 (16K)Sonar Reasoning ProQwen-MT Plus
Price50%72423
Inputs & features30%25350
Context window20%0240
Overall100%11/10027/10012/100

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 2 (16K) vs Sonar Reasoning Pro vs Qwen-MT Plus specifications side by side
SpecificationStep 2 (16K)StepFunSonar Reasoning ProPerplexityQwen-MT PlusAlibaba (Qwen)
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$5.21$2.00 (best)$2.46
Output$16.44$8.00$7.37 (best)
Cached input$1.04——
Blended (3:1)$8.02$3.50 (best)$3.69
Long-context rateSame rateSame rateSame rate
Price sourceOfficial StepFun (Global) APIOfficial Perplexity APIOfficial Alibaba API
Limits
Context window16,384 tokens128,000 tokens (best)16,384 tokens
Max output8,192 tokens (best)4,096 tokens8,192 tokens (best)
Inputs and features
TextYesYesYes
ImagesNoYesNo
PDFsNoNoNo
AudioNoNoNo
VideoNoNoNo
ReasoningNoYesminimal · low · medium · highNo
Tool callingYesNoNo
Structured outputNoNoNo
Availability
WeightsProprietaryProprietaryProprietary
API model IDstep-2-16ksonar-reasoning-proqwen-mt-plus
API providers14 (best)1
ReleasedJan 1, 2025Jan 1, 2024Jan 2025
Knowledge cutoffJun 2024Sep 1, 2025Apr 2024
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 2 (16K)$84.98
  • Sonar Reasoning Pro$36.00
  • Qwen-MT Plus$39.34
04 — Questions

Which should you choose?

Which is better: Step 2 (16K), Sonar Reasoning Pro or Qwen-MT Plus?

Sonar Reasoning Pro is the better all-round choice, scoring 27/100 against Qwen-MT Plus (12) and Step 2 (16K) (11). It leads on 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, Step 2 (16K), Sonar Reasoning Pro or Qwen-MT Plus?

Sonar Reasoning Pro is cheaper at $2.00 input / $8.00 output per million tokens (official Perplexity API price). Qwen-MT Plus costs $2.46 input / $7.37 output per million tokens (official Alibaba API price); Step 2 (16K) costs $5.21 input / $16.44 output per million tokens (official StepFun (Global) API price). At a typical mix of three input tokens to one output token, that is $3.50 per million tokens for Sonar Reasoning Pro versus $3.69 for Qwen-MT Plus (1.1× as much) and $8.02 for Step 2 (16K) (2.3× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. Step 2 (16K) has not been scored yet, Sonar Reasoning Pro has not been scored yet and Qwen-MT Plus has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for Step 2 (16K), Sonar Reasoning Pro and Qwen-MT Plus yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Note that Sonar Reasoning Pro and Qwen-MT Plus does not support tool calling, which most coding agents need.

Which has the bigger context window?

Sonar Reasoning Pro has the largest context window at 128,000 tokens, against 16,384 for Step 2 (16K) and 16,384 for Qwen-MT Plus. Maximum output per response: Step 2 (16K) up to 8,192, Sonar Reasoning Pro up to 4,096, Qwen-MT Plus up to 8,192 tokens.

Which can read images, PDFs, audio or video?

Step 2 (16K) accepts text; Sonar Reasoning Pro accepts text and images; Qwen-MT Plus accepts text. Sonar Reasoning Pro handles the widest range of inputs.

Are any of these open source?

No. Step 2 (16K), Sonar Reasoning Pro and Qwen-MT Plus are proprietary and only available through APIs and apps.

Which is newer?

Step 2 (16K) is the newest, released Jan 1, 2025. Qwen-MT Plus came out Jan 2025; Sonar Reasoning Pro came out Jan 1, 2024. Knowledge cutoff: Step 2 (16K) Jun 2024, Sonar Reasoning Pro Sep 1, 2025, Qwen-MT Plus Apr 2024.

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.