LLM Reference

DeepSeek V3 Base vs Qwen3.5-397B-A17B

DeepSeek V3 Base (2024) and Qwen3.5-397B-A17B (2026) are frontier reasoning models from DeepSeek and Alibaba. DeepSeek V3 Base ships a 128k-token context window, while Qwen3.5-397B-A17B ships a 262k-token context window. 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.

Qwen3.5-397B-A17B is safer overall; choose DeepSeek V3 Base when provider fit matters.

Decision scorecard

Local evidence first
SignalDeepSeek V3 BaseQwen3.5-397B-A17B
Best forgeneral production evaluationreasoning-heavy apps, multimodal apps, and tool-calling agents
Decision fitLong contextCoding, RAG, and Agents
Context window128k262k
Cheapest output-$2.34/1M tokens
Provider routes0 tracked4 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose DeepSeek V3 Base when...
  • Local decision data tags DeepSeek V3 Base for Long context.
Choose Qwen3.5-397B-A17B when...
  • Qwen3.5-397B-A17B has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Qwen3.5-397B-A17B has broader tracked provider coverage for fallback and procurement flexibility.
  • Qwen3.5-397B-A17B uniquely exposes Vision, Multimodal, and Reasoning in local model data.
  • 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.

DeepSeek V3 Base

Unavailable

No complete token price in local provider data

Qwen3.5-397B-A17B

$897

Cheapest tracked route/tier: OpenRouter

Cost delta unavailable until both models have sourced input and output token prices.

Switch friction

DeepSeek V3 Base -> Qwen3.5-397B-A17B
  • No overlapping tracked provider route is sourced for DeepSeek V3 Base and Qwen3.5-397B-A17B; plan for SDK, billing, or endpoint changes.
  • Qwen3.5-397B-A17B adds Vision, Multimodal, and Reasoning in local capability data.
Qwen3.5-397B-A17B -> DeepSeek V3 Base
  • No overlapping tracked provider route is sourced for Qwen3.5-397B-A17B and DeepSeek V3 Base; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Vision, Multimodal, and Reasoning before moving production traffic.

Specs

Specification
Released2024-12-262026-02-16
Context window128k262k
Parameters671B total, 37B active (MoE)397B
Architecturemixture of expertsMoE
LicenseMIT(OSI)Apache 2.0(OSI)
OpennessOpen sourceOpen source
Commercial useCommercial use allowedCommercial use allowed
Knowledge cutoff2024-07-

Pricing and availability

Pricing attributeDeepSeek V3 BaseQwen3.5-397B-A17B
Input price-$0.39/1M tokens
Output price-$2.34/1M tokens
Providers-

Capabilities

CapabilityDeepSeek V3 BaseQwen3.5-397B-A17B
VisionNoYes
MultimodalNoYes
ReasoningNoYes
Function callingNoYes
Tool useNoYes
Structured outputsNoYes
Code executionNoNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on vision: Qwen3.5-397B-A17B, multimodal input: Qwen3.5-397B-A17B, reasoning mode: Qwen3.5-397B-A17B, function calling: Qwen3.5-397B-A17B, tool use: Qwen3.5-397B-A17B, and structured outputs: Qwen3.5-397B-A17B. Both models share the core language-model surface, 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: DeepSeek V3 Base has no token price sourced yet and Qwen3.5-397B-A17B has $0.39/1M input tokens. Provider availability is 0 tracked routes versus 4. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose DeepSeek V3 Base when provider fit are central to the workload. Choose Qwen3.5-397B-A17B when reasoning depth, 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. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.

FAQ

Which has a larger context window, DeepSeek V3 Base or Qwen3.5-397B-A17B?

Qwen3.5-397B-A17B supports 262k tokens, while DeepSeek V3 Base supports 128k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Is DeepSeek V3 Base or Qwen3.5-397B-A17B open source?

DeepSeek V3 Base is listed under MIT. Qwen3.5-397B-A17B 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 Base or Qwen3.5-397B-A17B?

Qwen3.5-397B-A17B 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, DeepSeek V3 Base or Qwen3.5-397B-A17B?

Qwen3.5-397B-A17B 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 reasoning mode, DeepSeek V3 Base or Qwen3.5-397B-A17B?

Qwen3.5-397B-A17B has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run DeepSeek V3 Base and Qwen3.5-397B-A17B?

DeepSeek V3 Base is available on the tracked providers still being sourced. Qwen3.5-397B-A17B is available on OpenRouter, Together AI, Alibaba Cloud PAI-EAS, and Novita AI. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-04. Data sourced from public model cards and provider documentation.