ZMIME
Comparison · 2 models · Updated Oct 4, 2026

Qwen3.5 Plus vs o3

Qwen3.5 Plus comes out ahead, 66 to 58 on our weighted score, and it is the cheaper option too.

  1. Our pick

    Alibaba (Qwen)

    Qwen3.5 Plus

    Released Feb 16, 2026

    66/100
    • ECI146.8
    • Price$0.40 / $2.40
    • Context1M
    Full specs Remove Qwen3.5 Plus

  2. OpenAI

    o3

    Released Apr 16, 2025

    58/100
    • ECI146.9
    • Price$2.00 / $8.00
    • Context200K
    Full specs Remove o3

  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Qwen3.5 Plus is our pick

Qwen3.5 Plus is the better all-round choice, scoring 66/100 against o3 (58). It leads on price and context window. o3 wins on inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • Capabilityo3Capabilities Index (ECI): o3 146.9 · Qwen3.5 Plus 146.8
  • Lowest priceQwen3.5 PlusQwen3.5 Plus $0.90 · o3 $3.50 per 1M tokens (3:1 blend)
  • Longest contextQwen3.5 PlusQwen3.5 Plus 1,000,000 · o3 200,000 tokens
  • Widest inputsSame inputsQwen3.5 Plus: Text, Images, Video · o3: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightQwen3.5 Pluso3
CapabilityCapabilities Index (ECI)50%7474
Price25%5224
Inputs & features15%7080
Context window10%6032
Overall100%66/10058/100
02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Qwen3.5 Plus vs o3 specifications side by side
SpecificationQwen3.5 PlusAlibaba (Qwen)o3OpenAI
Capability
Capabilities Index (ECI)146.8146.9 (best)
ECI rank#65 of 148#63 of 148 (best)
GPQA DiamondGraduate-level science questions84.9% (best)81.8%
FrontierMath Tiers 1–3Research-level mathematics—33.3%
OTIS Mock AIME 2024–2025Competition mathematics86.7% (best)84.4%
SWE-bench VerifiedFixing real GitHub issues—62.3%
SimpleQA VerifiedShort factual questions25.4%49.4% (best)
Price per million tokens
Input$0.40 (best)$2.00
Output$2.40 (best)$8.00
Cached input—$0.50
Blended (3:1)$0.90 (best)$3.50
Long-context rateSame rateSame rate
Price sourceOfficial Alibaba APIOfficial OpenAI API
Limits
Context window1,000,000 tokens (best)200,000 tokens
Max output65,536 tokens100,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoYes
AudioNoNo
VideoYesNo
ReasoningYesYeslow · medium · high
Tool callingYesYes
Structured outputNoYes
Availability
WeightsProprietaryProprietary
API model IDqwen3.5-pluso3
API providers1018 (best)
ReleasedFeb 16, 2026Apr 16, 2025
Knowledge cutoffApr 2025May 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.

  • Qwen3.5 Plus$8.80
  • o3$36.00
04 — Questions

Which should you choose?

Which is better: Qwen3.5 Plus or o3?

Qwen3.5 Plus is the better all-round choice, scoring 66/100 against o3 (58). It leads on price and context window. o3 wins on inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Qwen3.5 Plus or o3?

Qwen3.5 Plus is cheaper at $0.40 input / $2.40 output per million tokens (official Alibaba API price). o3 costs $2.00 input / $8.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $0.90 per million tokens for Qwen3.5 Plus versus $3.50 for o3 (3.9× as much).

Which scores higher on benchmarks?

o3 scores higher on the Capabilities Index (ECI): o3 146.9 (#63 of 148) and Qwen3.5 Plus 146.8 (#65 of 148). The confidence ranges of the top two overlap (144.9–148.6 vs 144.6–148.1), so treat the gap as small. On individual benchmarks: GPQA Diamond — Qwen3.5 Plus 84.9%, o3 81.8%; OTIS Mock AIME 2024–2025 — Qwen3.5 Plus 86.7%, o3 84.4%; SimpleQA Verified — o3 49.4%, Qwen3.5 Plus 25.4%.

Which is better for coding?

There are no published SWE-bench Verified results for Qwen3.5 Plus yet, so there is no like-for-like coding score. On overall capability, o3 leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.

Which has the bigger context window?

Qwen3.5 Plus has the largest context window at 1,000,000 tokens, against 200,000 for o3. Maximum output per response: Qwen3.5 Plus up to 65,536, o3 up to 100,000 tokens.

Which can read images, PDFs, audio or video?

Qwen3.5 Plus accepts text, images and video; o3 accepts text, images and PDFs. They handle the same number of input types.

Are any of these open source?

No. Qwen3.5 Plus and o3 are proprietary and only available through APIs and apps.

Which is newer?

Qwen3.5 Plus is the newest, released Feb 16, 2026. o3 came out Apr 16, 2025. Knowledge cutoff: Qwen3.5 Plus Apr 2025, o3 May 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.

05 — Keep comparing

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