Qwen3.5 Flash vs DeepSeek V4 Flash
Qwen3.5 Flash comes out ahead, 75 to 71 on our weighted score.
- Our pick
Alibaba (Qwen)
Qwen3.5 Flash
75/100- ECI144.0
- Price$0.10 / $0.40
- Context1M
DeepSeek
DeepSeek V4 Flash
71/100- ECI146.1
- Price$0.14 / $0.28
- Context1M
Add a model
Make it a three-way comparison.
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
| Measure | Weight | Qwen3.5 Flash | DeepSeek V4 Flash |
|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 71 | 73 |
| Price | 25% | 86 | 86 |
| Inputs & features | 15% | 80 | 45 |
| Context window | 10% | 60 | 60 |
| Overall | 100% | 75/100 | 71/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | ||
|---|---|---|
| Capability | ||
| Capabilities Index (ECI) | 144.0 | 146.1 (best) |
| ECI rank | #82 of 148 | #71 of 148 (best) |
| GPQA DiamondGraduate-level science questions | 82.3% | — |
| FrontierMath Tiers 1–3Research-level mathematics | 18.3% | — |
| OTIS Mock AIME 2024–2025Competition mathematics | 84.4% | — |
| SimpleQA VerifiedShort factual questions | 20.3% | — |
| 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 rate | Same rate | Same rate |
| Price source | Official Alibaba API | Median of 42 providers |
| Limits | ||
| Context window | 1,000,000 tokens | 1,000,000 tokens |
| Max output | 65,536 tokens | 384,000 tokens (best) |
| Inputs and features | ||
| Text | Yes | Yes |
| Images | Yes | No |
| PDFs | No | No |
| Audio | No | No |
| Video | Yes | No |
| Reasoning | Yes | Yes |
| Tool calling | Yes | Yes |
| Structured output | Yes | Yes |
| Availability | ||
| Weights | Proprietary | Open |
| API model ID | qwen3.5-flash | — |
| API providers | 8 | 48 (best) |
| Released | Feb 23, 2026 | Apr 24, 2026 |
| Knowledge cutoff | — | May 2025 |
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
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.