DeepSeek V3.1 vs Qwen3.5-9B
DeepSeek V3.1 (2025) and Qwen3.5-9B (2026) are compact production models from DeepSeek and Alibaba. DeepSeek V3.1 ships a 64K-token context window, while Qwen3.5-9B ships a 262K-token context window. On MMLU PRO, DeepSeek V3.1 leads by a hair. On pricing, Qwen3.5-9B costs $0.10/1M input tokens versus $0.27/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.
Qwen3.5-9B is ~170% cheaper at $0.10/1M; pay for DeepSeek V3.1 only for coding workflow support.
Decision scorecard
Local evidence first| Signal | DeepSeek V3.1 | Qwen3.5-9B |
|---|---|---|
| Best for | multimodal apps and provider-routed production | multimodal apps, tool-calling agents, and provider-routed production |
| Decision fit | Coding, Agents, and Vision | RAG, Agents, and Long context |
| Context window | 64K | 262K |
| Cheapest output | $1/1M tokens | $0.15/1M tokens |
| Provider routes | 8 tracked | 3 tracked |
| Shared benchmarks | MMLU PRO leader | 1 rows |
Decision tradeoffs
- DeepSeek V3.1 leads the largest shared benchmark signal on MMLU PRO by 0.8 points.
- DeepSeek V3.1 has broader tracked provider coverage for fallback and procurement flexibility.
- DeepSeek V3.1 uniquely exposes Code execution in local model data.
- Local decision data tags DeepSeek V3.1 for Coding, Agents, and Vision.
- Qwen3.5-9B has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Qwen3.5-9B has the lower cheapest tracked output price at $0.15/1M tokens.
- Qwen3.5-9B uniquely exposes Function calling 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 route or tier on this page.
DeepSeek V3.1
$466
Cheapest tracked route/tier: Novita AI
Qwen3.5-9B
$118
Cheapest tracked route/tier: Together AI
Estimated monthly gap: $349. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on Together AI; start route-level A/B tests there.
- Qwen3.5-9B is $0.85/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Code execution before moving production traffic.
- Qwen3.5-9B adds Function calling and Tool use in local capability data.
- Provider overlap exists on Together AI; start route-level A/B tests there.
- DeepSeek V3.1 is $0.85/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Check replacement coverage for Function calling and Tool use before moving production traffic.
- DeepSeek V3.1 adds Code execution in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-08-21 | 2026-03-02 |
| Context window | 64K | 262K |
| Parameters | 671B total, 37B active (MoE) | 9B |
| Architecture | mixture of experts | decoder only |
| License | Proprietary | Apache 2.0 |
| Knowledge cutoff | - | - |
Pricing and availability
| Pricing attribute | DeepSeek V3.1 | Qwen3.5-9B |
|---|---|---|
| Input price | $0.27/1M tokens | $0.10/1M tokens |
| Output price | $1/1M tokens | $0.15/1M tokens |
| Providers |
Capabilities
| Capability | DeepSeek V3.1 | Qwen3.5-9B |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | No | No |
| Function calling | No | Yes |
| Tool use | No | Yes |
| Structured outputs | Yes | Yes |
| Code execution | Yes | No |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
| Benchmark | DeepSeek V3.1 | Qwen3.5-9B |
|---|---|---|
| MMLU PRO | 83.3 | 82.5 |
Deep dive
On shared benchmark coverage, MMLU PRO has DeepSeek V3.1 at 83.3 and Qwen3.5-9B at 82.5, with DeepSeek V3.1 ahead by 0.8 points. The largest visible gap is 0.8 points on MMLU PRO, 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 function calling: Qwen3.5-9B, tool use: Qwen3.5-9B, and code execution: DeepSeek V3.1. Both models share vision, multimodal input, and structured outputs, 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.
For cost, DeepSeek V3.1 lists $0.27/1M input and $1/1M output tokens on the cheapest tracked provider, while Qwen3.5-9B lists $0.10/1M input and $0.15/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Qwen3.5-9B lower by about $0.37 per million blended tokens. Availability is 8 providers versus 3, so concentration risk also matters.
Choose DeepSeek V3.1 when coding workflow support and broader provider choice are central to the workload. Choose Qwen3.5-9B when long-context analysis, larger context windows, and lower input-token cost 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, DeepSeek V3.1 or Qwen3.5-9B?
Qwen3.5-9B supports 262K tokens, while DeepSeek V3.1 supports 64K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is cheaper, DeepSeek V3.1 or Qwen3.5-9B?
Qwen3.5-9B is cheaper on tracked token pricing. DeepSeek V3.1 costs $0.27/1M input and $1/1M output tokens. Qwen3.5-9B costs $0.10/1M input and $0.15/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is DeepSeek V3.1 or Qwen3.5-9B open source?
DeepSeek V3.1 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, DeepSeek V3.1 or Qwen3.5-9B?
Both DeepSeek V3.1 and Qwen3.5-9B expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for multimodal input, DeepSeek V3.1 or Qwen3.5-9B?
Both DeepSeek V3.1 and Qwen3.5-9B expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Where can I run DeepSeek V3.1 and Qwen3.5-9B?
DeepSeek V3.1 is available on Microsoft Foundry, Fireworks AI, NVIDIA NIM, Together AI, and AWS Bedrock. 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: 2026-05-22. Data sourced from public model cards and provider documentation.