Seed 2.1 Turbo vs Qwen3.5 27B
Qwen3.5 27B comes out ahead, 61 to 57 on our weighted score, and it is the cheaper option too.
ByteDance SeedSeed 2.1 Turbo
57/100- ECI—
- Price$0.445 / $2.23
- Context256K
- Our pick
Alibaba (Qwen)Qwen3.5 27B
61/100- ECI—
- Price$0.30 / $2.40
- Context262K
Add a model
Make it a three-way comparison.
Qwen3.5 27B is our pick
Qwen3.5 27B is the better all-round choice, scoring 61/100 against Seed 2.1 Turbo (57). It leads on price and inputs & features. 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 priceQwen3.5 27BQwen3.5 27B $0.825 · Seed 2.1 Turbo $0.891 per 1M tokens (3:1 blend)
- Longest contextQwen3.5 27BQwen3.5 27B 262,144 · Seed 2.1 Turbo 256,000 tokens
- Widest inputsQwen3.5 27BSeed 2.1 Turbo: Text, Images, Video · Qwen3.5 27B: Text, Images, Audio, Video
- Self-hostingQwen3.5 27BPublishes downloadable weights
| Measure | Weight | Seed 2.1 Turbo | Qwen3.5 27B |
|---|---|---|---|
| Price | 50% | 52 | 54 |
| Inputs & features | 30% | 80 | 90 |
| Context window | 20% | 36 | 37 |
| Overall | 100% | 57/100 | 61/100 |
Left out because at least one model lacks the data: capability. The remaining weights were rescaled.
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | Seed 2.1 TurboByteDance Seed | Qwen3.5 27BAlibaba (Qwen) |
|---|---|---|
| Capability | ||
| Capabilities Index (ECI) | — | — |
| ECI rank | — | — |
| Price per million tokens | ||
| Input | $0.445 | $0.30 (best) |
| Output | $2.23 (best) | $2.40 |
| Cached input | $0.089 | — |
| Blended (3:1) | $0.891 | $0.825 (best) |
| Long-context rate | Same rate | Same rate |
| Price source | Official Volcengine Ark API | Official Alibaba API |
| Limits | ||
| Context window | 256,000 tokens | 262,144 tokens (best) |
| Max output | 256,000 tokens (best) | 65,536 tokens |
| Inputs and features | ||
| Text | Yes | Yes |
| Images | Yes | Yes |
| PDFs | No | No |
| Audio | No | Yes |
| Video | Yes | Yes |
| Reasoning | Yesminimal · low · medium · high · xhigh · max | Yes |
| Tool calling | Yes | Yes |
| Structured output | Yes | Yes |
| Availability | ||
| Weights | Proprietary | Open |
| API model ID | doubao-seed-2-1-turbo-260628 | qwen3.5-27b |
| API providers | 4 | 16 (best) |
| Released | Jun 23, 2026 | Feb 23, 2026 |
| Knowledge cutoff | — | — |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- Seed 2.1 Turbo$8.91
- Qwen3.5 27B$7.80
Which should you choose?
Which is better: Seed 2.1 Turbo or Qwen3.5 27B?
Qwen3.5 27B is the better all-round choice, scoring 61/100 against Seed 2.1 Turbo (57). It leads on price and inputs & features. 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, Seed 2.1 Turbo or Qwen3.5 27B?
Qwen3.5 27B is cheaper at $0.30 input / $2.40 output per million tokens (official Alibaba API price). Seed 2.1 Turbo costs $0.445 input / $2.23 output per million tokens (official Volcengine Ark API price). At a typical mix of three input tokens to one output token, that is $0.825 per million tokens for Qwen3.5 27B versus $0.891 for Seed 2.1 Turbo (1.1× as much).
Which scores higher on benchmarks?
There is no independent benchmark that covers both models yet. Seed 2.1 Turbo has not been scored yet and Qwen3.5 27B has not been scored yet.
Which is better for coding?
There are no published SWE-bench Verified results for Seed 2.1 Turbo and Qwen3.5 27B yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Both support tool calling for agent workflows.
Which has the bigger context window?
Qwen3.5 27B has the largest context window at 262,144 tokens, against 256,000 for Seed 2.1 Turbo. Maximum output per response: Seed 2.1 Turbo up to 256,000, Qwen3.5 27B up to 65,536 tokens.
Which can read images, PDFs, audio or video?
Seed 2.1 Turbo accepts text, images and video; Qwen3.5 27B accepts text, images, audio and video. Qwen3.5 27B handles the widest range of inputs.
Are any of these open source?
Qwen3.5 27B publishes its weights and can be self-hosted; Seed 2.1 Turbo is proprietary.
Which is newer?
Seed 2.1 Turbo is the newest, released Jun 23, 2026. Qwen3.5 27B came out Feb 23, 2026.
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.
