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Comparison · 2 models · Updated Oct 4, 2026

Qwen3.5 Flash vs DeepSeek V4 Flash

Qwen3.5 Flash comes out ahead, 75 to 71 on our weighted score.

  1. Our pick

    Alibaba (Qwen)

    Qwen3.5 Flash

    Released Feb 23, 2026

    75/100
    • ECI144.0
    • Price$0.10 / $0.40
    • Context1M
  2. DeepSeek

    DeepSeek V4 Flash

    Released Apr 24, 2026

    71/100
    • ECI146.1
    • Price$0.14 / $0.28
    • Context1M
  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Qwen3.5 Flash is our pick

Qwen3.5 Flash is the better all-round choice, scoring 75/100 against DeepSeek V4 Flash (71). It leads on inputs & features. DeepSeek V4 Flash wins on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityDeepSeek V4 FlashCapabilities Index (ECI): DeepSeek V4 Flash 146.1 · Qwen3.5 Flash 144.0
  • Lowest priceSame priceQwen3.5 Flash $0.175 · DeepSeek V4 Flash $0.175 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameQwen3.5 Flash 1,000,000 · DeepSeek V4 Flash 1,000,000 tokens
  • Widest inputsQwen3.5 FlashQwen3.5 Flash: Text, Images, Video · DeepSeek V4 Flash: Text
  • Self-hostingDeepSeek V4 FlashPublishes downloadable weights
How the score is built
MeasureWeightQwen3.5 FlashDeepSeek V4 Flash
CapabilityCapabilities Index (ECI)50%7173
Price25%8686
Inputs & features15%8045
Context window10%6060
Overall100%75/10071/100
02 — Side by side

Every spec in one table

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

Qwen3.5 Flash vs DeepSeek V4 Flash specifications side by side
SpecificationQwen3.5 FlashAlibaba (Qwen)DeepSeek V4 FlashDeepSeek
Capability
Capabilities Index (ECI)144.0146.1 (best)
ECI rank#82 of 148#71 of 148 (best)
GPQA DiamondGraduate-level science questions82.3%—
FrontierMath Tiers 1–3Research-level mathematics18.3%—
OTIS Mock AIME 2024–2025Competition mathematics84.4%—
SimpleQA VerifiedShort factual questions20.3%—
Price per million tokens
Input$0.10 (best)$0.14
Output$0.40$0.28 (best)
Cached input$0.01—
Blended (3:1)$0.175$0.175
Long-context rateSame rateSame rate
Price sourceOfficial Alibaba APIMedian of 42 providers
Limits
Context window1,000,000 tokens1,000,000 tokens
Max output65,536 tokens384,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesNo
PDFsNoNo
AudioNoNo
VideoYesNo
ReasoningYesYes
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryOpen
API model IDqwen3.5-flash—
API providers848 (best)
ReleasedFeb 23, 2026Apr 24, 2026
Knowledge cutoff—May 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.

  • Qwen3.5 Flash$1.80
  • DeepSeek V4 Flash$1.96
04 — Questions

Which should you choose?

Which is better: Qwen3.5 Flash or DeepSeek V4 Flash?

Qwen3.5 Flash is the better all-round choice, scoring 75/100 against DeepSeek V4 Flash (71). It leads on inputs & features. DeepSeek V4 Flash wins on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Qwen3.5 Flash or DeepSeek V4 Flash?

Qwen3.5 Flash and DeepSeek V4 Flash cost the same: $0.10 input / $0.40 output per million tokens.

Which scores higher on benchmarks?

DeepSeek V4 Flash scores higher on the Capabilities Index (ECI): DeepSeek V4 Flash 146.1 (#71 of 148) and Qwen3.5 Flash 144.0 (#82 of 148). The confidence ranges of the top two overlap (143.6–147.9 vs 141.6–145.5), so treat the gap as small.

Which is better for coding?

There are no published SWE-bench Verified results for Qwen3.5 Flash and DeepSeek V4 Flash yet, so there is no like-for-like coding score. On overall capability, DeepSeek V4 Flash 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 Flash and DeepSeek V4 Flash share the same 1,000,000-token context window. Maximum output per response: Qwen3.5 Flash up to 65,536, DeepSeek V4 Flash up to 384,000 tokens.

Which can read images, PDFs, audio or video?

Qwen3.5 Flash accepts text, images and video; DeepSeek V4 Flash accepts text. Qwen3.5 Flash handles the widest range of inputs.

Are any of these open source?

DeepSeek V4 Flash publishes its weights and can be self-hosted; Qwen3.5 Flash is proprietary.

Which is newer?

DeepSeek V4 Flash is the newest, released Apr 24, 2026. Qwen3.5 Flash came out Feb 23, 2026. Knowledge cutoff: DeepSeek V4 Flash May 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.