Claude Sonnet 4.5 vs Qwen3.5-397B-A17B
Claude Sonnet 4.5 (2025) and Qwen3.5-397B-A17B (2026) are frontier-tier reasoning models from Anthropic and Alibaba. Claude Sonnet 4.5 ships a 200k-token context window, while Qwen3.5-397B-A17B ships a 262k-token context window. On MMLU PRO, Qwen3.5-397B-A17B leads by 1.8 pts. On pricing, Claude Sonnet 4.5 ranges from $3 to $6/1M input tokens by tier; Qwen3.5-397B-A17B costs $0.39/1M input tokens. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
Qwen3.5-397B-A17B is safer overall; choose Claude Sonnet 4.5 when vision-heavy evaluation matters.
Decision scorecard
Local evidence first| Signal | Claude Sonnet 4.5 | Qwen3.5-397B-A17B |
|---|---|---|
| Best for | reasoning-heavy apps, multimodal apps, and tool-calling agents | reasoning-heavy apps, multimodal apps, and tool-calling agents |
| Decision fit | Coding, RAG, and Agents | Coding, RAG, and Agents |
| Context window | 200k | 262k |
| Cheapest output | $15/1M tokens | $2.34/1M tokens |
| Provider routes | 8 tracked | 4 tracked |
| Shared benchmarks | 5 shared | MMLU PRO leader |
Decision tradeoffs
- Claude Sonnet 4.5 holds a shared-benchmark lead on SWE-bench Verified, ahead by 1 points.
- Claude Sonnet 4.5 has broader tracked provider coverage for fallback and route flexibility.
- Local decision data tags Claude Sonnet 4.5 for Coding, RAG, and Agents.
- Qwen3.5-397B-A17B holds a shared-benchmark lead on MMLU PRO, ahead by 1.8 points.
- Qwen3.5-397B-A17B has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Qwen3.5-397B-A17B has the lower cheapest tracked output price at $2.34/1M tokens.
- Local decision data tags Qwen3.5-397B-A17B 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.
Claude Sonnet 4.5
$6,150
Cheapest tracked route/tier: Microsoft Foundry
Qwen3.5-397B-A17B
$897
Cheapest tracked route/tier: OpenRouter
Estimated monthly gap: $5,253. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on OpenRouter; start route-level A/B tests there.
- Qwen3.5-397B-A17B is $12.66/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Provider overlap exists on OpenRouter; start route-level A/B tests there.
- Claude Sonnet 4.5 is $12.66/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-09-29 | 2026-02-16 |
| Context window | 200k | 262k |
| Parameters | — | 397B |
| Architecture | Decoder Only | Mixture of Experts |
| License | Proprietary | Apache 2.0OSI-approved |
| Openness | Proprietary | Open source |
| Weights | Not released | Available |
| Code | Unknown | Unknown |
| Commercial use | Commercial use: conditional | Commercial use: permitted |
| Knowledge cutoff | 2025-12 | - |
Pricing and availability
| Pricing attribute | Claude Sonnet 4.5 | Qwen3.5-397B-A17B |
|---|---|---|
| Input price |
| $0.39/1M tokens |
| Output price |
| $2.34/1M tokens |
| Providers |
Capabilities
| Capability | Claude Sonnet 4.5 | Qwen3.5-397B-A17B |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | Yes |
| JSON / Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | No | No |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
| Benchmark | Claude Sonnet 4.5 | Qwen3.5-397B-A17B |
|---|---|---|
| MMLU PRO | 86.0 | 87.8 |
| SWE-bench Verified | 77.2 | 76.2 |
| Google-Proof Q&A | 83.4 | 89.3 |
| Massive Multi-discipline Multimodal Understanding | 77.8 | 85.0 |
| BFCL | 73.2 | 72.9 |
Continue comparing
Popular comparisons for Claude Sonnet 4.5
Popular comparisons for Qwen3.5-397B-A17B
Last reviewed: 2026-07-26. Data sourced from public model cards and provider documentation.