ByteDance Doubao Seed 2.0 Pro vs Qwen3.5-9B
ByteDance Doubao Seed 2.0 Pro (2026) and Qwen3.5-9B (2026) are general-purpose language models from ByteDance and Alibaba. ByteDance Doubao Seed 2.0 Pro ships a 256k-token context window, while Qwen3.5-9B ships a 262K-token context window. On MMLU PRO, ByteDance Doubao Seed 2.0 Pro leads by 4.5 pts. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing.
Qwen3.5-9B is safer overall; choose ByteDance Doubao Seed 2.0 Pro when provider fit matters.
Decision scorecard
Local evidence first| Signal | ByteDance Doubao Seed 2.0 Pro | Qwen3.5-9B |
|---|---|---|
| Decision fit | Coding, RAG, and Agents | RAG, Agents, and Long context |
| Context window | 256k | 262K |
| Cheapest output | - | $0.15/1M tokens |
| Provider routes | 0 tracked | 3 tracked |
| Shared benchmarks | MMLU PRO leader | 2 rows |
Decision tradeoffs
- ByteDance Doubao Seed 2.0 Pro leads the largest shared benchmark signal on MMLU PRO by 4.5 points.
- Local decision data tags ByteDance Doubao Seed 2.0 Pro for Coding, RAG, and Agents.
- Qwen3.5-9B has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Qwen3.5-9B has broader tracked provider coverage for fallback and procurement flexibility.
- Qwen3.5-9B uniquely exposes Vision, Multimodal, and Tool use in local model data.
- Local decision data tags Qwen3.5-9B for RAG, Agents, and Long context.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output prices on this page.
ByteDance Doubao Seed 2.0 Pro
Unavailable
No complete token price in local provider data
Qwen3.5-9B
$118
Cheapest tracked route: Together AI
Cost delta unavailable until both models have sourced input and output token prices.
Switch friction
- No overlapping tracked provider route is sourced for ByteDance Doubao Seed 2.0 Pro and Qwen3.5-9B; plan for SDK, billing, or endpoint changes.
- Qwen3.5-9B adds Vision, Multimodal, and Tool use in local capability data.
- No overlapping tracked provider route is sourced for Qwen3.5-9B and ByteDance Doubao Seed 2.0 Pro; plan for SDK, billing, or endpoint changes.
- Check replacement coverage for Vision, Multimodal, and Tool use before moving production traffic.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-02-14 | 2026-03-02 |
| Context window | 256k | 262K |
| Parameters | — | 9B |
| Architecture | - | decoder only |
| License | Proprietary | Apache 2.0 |
| Knowledge cutoff | - | - |
Pricing and availability
| Pricing attribute | ByteDance Doubao Seed 2.0 Pro | Qwen3.5-9B |
|---|---|---|
| Input price | - | $0.1/1M tokens |
| Output price | - | $0.15/1M tokens |
| Providers | - |
Capabilities
| Capability | ByteDance Doubao Seed 2.0 Pro | Qwen3.5-9B |
|---|---|---|
| Vision | No | Yes |
| Multimodal | No | Yes |
| Reasoning | No | No |
| Function calling | Yes | Yes |
| Tool use | No | Yes |
| Structured outputs | No | Yes |
| Code execution | No | No |
Benchmarks
| Benchmark | ByteDance Doubao Seed 2.0 Pro | Qwen3.5-9B |
|---|---|---|
| MMLU PRO | 87.0 | 82.5 |
| Google-Proof Q&A | 88.9 | 81.7 |
Deep dive
On shared benchmark coverage, MMLU PRO has ByteDance Doubao Seed 2.0 Pro at 87 and Qwen3.5-9B at 82.5, with ByteDance Doubao Seed 2.0 Pro ahead by 4.5 points; Google-Proof Q&A has ByteDance Doubao Seed 2.0 Pro at 88.9 and Qwen3.5-9B at 81.7, with ByteDance Doubao Seed 2.0 Pro ahead by 7.2 points. The largest visible gap is 7.2 points on Google-Proof Q&A, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint differs most on vision: Qwen3.5-9B, multimodal input: Qwen3.5-9B, tool use: Qwen3.5-9B, and structured outputs: Qwen3.5-9B. Both models share function calling, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
Pricing coverage is uneven: ByteDance Doubao Seed 2.0 Pro has no token price sourced yet and Qwen3.5-9B has $0.1/1M input tokens. Provider availability is 0 tracked routes versus 3. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.
Choose ByteDance Doubao Seed 2.0 Pro when provider fit are central to the workload. Choose Qwen3.5-9B when long-context analysis, larger context windows, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which has a larger context window, ByteDance Doubao Seed 2.0 Pro or Qwen3.5-9B?
Qwen3.5-9B supports 262K tokens, while ByteDance Doubao Seed 2.0 Pro supports 256k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Is ByteDance Doubao Seed 2.0 Pro or Qwen3.5-9B open source?
ByteDance Doubao Seed 2.0 Pro is listed under Proprietary. Qwen3.5-9B is listed under Apache 2.0. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, ByteDance Doubao Seed 2.0 Pro or Qwen3.5-9B?
Qwen3.5-9B has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for multimodal input, ByteDance Doubao Seed 2.0 Pro or Qwen3.5-9B?
Qwen3.5-9B has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for function calling, ByteDance Doubao Seed 2.0 Pro or Qwen3.5-9B?
Both ByteDance Doubao Seed 2.0 Pro and Qwen3.5-9B expose function calling. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Where can I run ByteDance Doubao Seed 2.0 Pro and Qwen3.5-9B?
ByteDance Doubao Seed 2.0 Pro is available on the tracked providers still being sourced. Qwen3.5-9B is available on Together AI, OpenRouter, and Alibaba Cloud PAI-EAS. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-14. Data sourced from public model cards and provider documentation.