Qwen2.5-72B vs Qwen3.5-9B
Qwen2.5-72B (2025) and Qwen3.5-9B (2026) are compact production models from Alibaba. Qwen2.5-72B ships a 128k-token context window, while Qwen3.5-9B ships a 262k-token context window. On MMLU PRO, Qwen3.5-9B leads by 10.5 pts. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads. It focuses on practical selection signals rather than broad model-family marketing.
Qwen3.5-9B is safer overall; choose Qwen2.5-72B when provider fit matters.
Decision scorecard
Local evidence first| Signal | Qwen2.5-72B | Qwen3.5-9B |
|---|---|---|
| Best for | tool-calling agents | multimodal apps, tool-calling agents, and provider-routed production |
| Decision fit | RAG, Agents, and Long context | Coding, RAG, and Agents |
| Context window | 128k | 262k |
| Cheapest output | - | $0.15/1M tokens |
| Provider routes | 0 tracked | 3 tracked |
| Shared benchmarks | 1 rows | MMLU PRO leader |
Decision tradeoffs
- Local decision data tags Qwen2.5-72B for RAG, Agents, and Long context.
- Qwen3.5-9B holds a shared-benchmark lead on MMLU PRO, ahead by 10.5 points.
- 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 Structured outputs in local model data.
- Local decision data tags Qwen3.5-9B for Coding, RAG, and Agents.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Qwen2.5-72B
Unavailable
No complete token price in local provider data
Qwen3.5-9B
$118
Cheapest tracked route/tier: 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 Qwen2.5-72B and Qwen3.5-9B; plan for SDK, billing, or endpoint changes.
- Qwen3.5-9B adds Vision, Multimodal, and Structured outputs in local capability data.
- No overlapping tracked provider route is sourced for Qwen3.5-9B and Qwen2.5-72B; plan for SDK, billing, or endpoint changes.
- Check replacement coverage for Vision, Multimodal, and Structured outputs before moving production traffic.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-10-10 | 2026-03-02 |
| Context window | 128k | 262k |
| Parameters | 72B | 9B |
| Architecture | - | decoder only |
| License | Apache 2.0(OSI) | Apache 2.0(OSI) |
| Openness | Open source | Open source |
| Commercial use | Commercial use allowed | Commercial use allowed |
| Knowledge cutoff | 2024-09 | - |
Pricing and availability
| Pricing attribute | Qwen2.5-72B | Qwen3.5-9B |
|---|---|---|
| Input price | - | $0.10/1M tokens |
| Output price | - | $0.15/1M tokens |
| Providers | - |
Capabilities
| Capability | Qwen2.5-72B | Qwen3.5-9B |
|---|---|---|
| Vision | No | Yes |
| Multimodal | No | Yes |
| Reasoning | No | No |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | No | Yes |
| Code execution | No | No |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
| Benchmark | Qwen2.5-72B | Qwen3.5-9B |
|---|---|---|
| MMLU PRO | 72.0 | 82.5 |
Deep dive
On shared benchmark coverage, MMLU PRO has Qwen2.5-72B at 72 and Qwen3.5-9B at 82.5, with Qwen3.5-9B ahead by 10.5 points. The largest visible gap is 10.5 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 vision: Qwen3.5-9B, multimodal input: Qwen3.5-9B, and structured outputs: Qwen3.5-9B. Both models share function calling and tool use, 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: Qwen2.5-72B has no token price sourced yet and Qwen3.5-9B has $0.10/1M 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 Qwen2.5-72B 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, Qwen2.5-72B or Qwen3.5-9B?
Qwen3.5-9B supports 262k tokens, while Qwen2.5-72B supports 128k 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.
Is Qwen2.5-72B or Qwen3.5-9B open source?
Qwen2.5-72B is listed under Apache 2.0. 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, Qwen2.5-72B 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, Qwen2.5-72B 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, Qwen2.5-72B or Qwen3.5-9B?
Both Qwen2.5-72B 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. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Where can I run Qwen2.5-72B and Qwen3.5-9B?
Qwen2.5-72B 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: 2026-05-19. Data sourced from public model cards and provider documentation.