Compare / Qwen3.5-397B-A17B vs DeepSeek-V3.1-Terminus

Qwen3.5-397B-A17B vs DeepSeek-V3.1-Terminus

Which is cheaper, which is more capable, and which does better at each kind of work, from 20 results on 3 sources that measured both models.

AlibabaQwen3.5-397B-A17B Released 13 Feb 2026 · $0.55 in · $3.50 out
DeepSeekDeepSeek-V3.1-Terminus Released 22 Sep 2025 · $0.27 in · $1.00 out
Qwen3.5-397B-A17B wins 125 too close to callDeepSeek-V3.1-Terminus wins 3

Of the 20 results both models have, the better value on each. Results whose reported ranges overlap are too close to call.

Results as of 13 October 2026 (catalogue release 2026-10-13-2e2420e3c5cc). See also Alibaba vs DeepSeek, every model from both labs.

Qwen3.5-397B-A17B or DeepSeek-V3.1-Terminus? The short answer

Pick Qwen3.5-397B-A17B if quality matters most: it scores higher (Intelligence Index 21.4 against 14.8). Pick DeepSeek-V3.1-Terminus if cost matters more: it costs 2.8 times less per token.

  • DeepSeek-V3.1-Terminus is cheaper: $0.45 against $1.29 per million tokens, 2.8 times less.
  • Qwen3.5-397B-A17B scores higher on the Artificial Analysis Intelligence Index: 21.4 against 14.8.
  • Qwen3.5-397B-A17B is newer: released 13 Feb 2026, against 22 Sep 2025 for DeepSeek-V3.1-Terminus.
  • On third-party benchmarks, on the results both models have: Qwen3.5-397B-A17B does better for reasoning and knowledge.

Head to head

21.4
Intelligence Index
14.8
$1.29
Price per million tokens, blendedlower is better
$0.45
262,144
Context window, tokens
163,840

Every fact side by side

Qwen3.5-397B-A17BDeepSeek-V3.1-Terminus
Price per million tokens$0.55 in · $3.50 out$0.27 in · $1.00 out
Blended (3 in : 1 out)$1.29$0.45
Cheapest host, blended$0.88 (Alibaba)$0.45 (SiliconFlow, FP8)
Intelligence Index21.414.8
Spring Prompt overall––
Output speed, tokens a second90–
Context window262,144 tokens163,840 tokens
Released13 Feb 2026 (newer)22 Sep 2025
WeightsOpenOpen
Developer based inChinaChina

Prices are the developer's list price where we have read it, otherwise the typical host on OpenRouter; see every model's price. Intelligence and speed from Artificial Analysis.

Which is better for what

Each model's rank among the models on sale today, for each kind of work, from our own benchmarks and licensed sources. Further right is better; the better rank is in green.

Agents and tool useMulti-step tasks with tools: support desks, coding agents, function calls 70 of 164 88 of 164
Professional workReal tasks from banking, consulting and law, business documents and freelance projects 48 of 51 not measured
Reasoning and knowledgeHard questions across science, maths and general knowledge 73 of 198 109 of 198
WritingWhat people prefer in blind comparisons, and judged writing quality 69 of 188 81 of 188
Sticking to the factsSummarising without inventing things, and factual answers 75 of 152 not measured

Every shared result

Each model's best result on every measure both have, grouped by benchmark, with the setting that produced it. Under each measure, every model that benchmark has measured is a grey tick, best to the right, so you can see where the two sit in the field. The headline measures of each benchmark come first; the rest are under "Show all". Green marks the better value; where a source reports ranges that overlap, neither is marked.

MeasureQwen3.5-397B-A17BDeepSeek-V3.1-Terminus
Arena (formerly LMArena) reported by Arena (formerly LMArena) · 3 results
Overall · TextArena rating, higher is better 80 · 115 of 387 measured 1,442 1,417thinking reasoning
Business, management and finance · TextArena rating, higher is better 73 · 103 of 380 measured 1,446 1,423thinking reasoning
Creative writing · TextArena rating, higher is better 86 · 87 of 385 measured 1,405 1,405
Artificial Analysis reported by Artificial Analysis · 3 results
Artificial Analysis Intelligence Indexindex score, higher is better 97 · 129 of 243 measured 21.4no reasoning 14.8thinking reasoning
GPQA Diamond% of questions, higher is better 53 · 112 of 231 measured 89.3% 79.2%thinking reasoning
Humanity's Last Exam% of questions, higher is better 77 · 121 of 242 measured 29.0% 16.4%thinking reasoning
UGI Leaderboard reported by UGI Leaderboard · 3 results
Writing score · UGIscore out of 100, higher is better 77 · 64 of 230 measured 50.1no reasoning 54.0thinking reasoning
Requested-length error · UGI% off the requested word count, lower is better 134 · 174 of 230 measured 23.0%no reasoning 32.0%thinking reasoning
Style adherence · UGIscore from 0 to 1, higher is better 164 · 43 of 230 measured 0.33no reasoning 0.37thinking reasoning
Show all 20 results (11 more)
MeasureQwen3.5-397B-A17BDeepSeek-V3.1-Terminus
Arena (formerly LMArena) reported by Arena (formerly LMArena) · 2 results
Instruction following · TextArena rating, higher is better 78 · 93 of 387 measured 1,434 1,420thinking reasoning
Writing, literature and language · TextArena rating, higher is better 80 · 88 of 386 measured 1,421 1,412thinking reasoning
Artificial Analysis reported by Artificial Analysis · 9 results
Terminal-Bench 2.1% of tasks, higher is better 61 · 68 of 130 measured 51.3% 44.9%thinking reasoning
Terminal-Bench 4.0% of tasks, higher is better 66 · 66 of 112 measured 0.0% 0.0%thinking reasoning
τ-bench banking% of tasks, higher is better 64 · 47 of 121 measured 13.4% 21.0%thinking reasoning
Artificial Analysis Coding Indexindex score, higher is better 61 · 69 of 131 measured 48.2 43.5thinking reasoning
IFBench% of instructions, higher is better 8 · 86 of 195 measured 78.8% 57.0%thinking reasoning
Long-context reasoning (AA-LCR)% of questions, higher is better 66 · 113 of 233 measured 77.3% 69.3%thinking reasoning
SciCode% of problems, higher is better 66 · 85 of 113 measured 44.8% 38.0%thinking reasoning
Terminal-Bench Hard% of tasks, higher is better 34 · 63 of 190 measured 40.9% 31.8%no reasoning
τ²-bench telecom% of tasks, higher is better 16 · 118 of 193 measured 95.6% 37.1%no reasoning

Quick answers

Is Qwen3.5-397B-A17B better than DeepSeek-V3.1-Terminus?

Pick Qwen3.5-397B-A17B if quality matters most: it scores higher (Intelligence Index 21.4 against 14.8). Pick DeepSeek-V3.1-Terminus if cost matters more: it costs 2.8 times less per token.

Which is cheaper, Qwen3.5-397B-A17B or DeepSeek-V3.1-Terminus?

DeepSeek-V3.1-Terminus is cheaper: $0.45 against $1.29 per million tokens, 2.8 times less.

Which is better for agents and tool use, Qwen3.5-397B-A17B or DeepSeek-V3.1-Terminus?

Qwen3.5-397B-A17B ranks 70 of 164 models on sale for multi-step tasks with tools: support desks, coding agents, function calls, against 88 for DeepSeek-V3.1-Terminus.

Which is better for reasoning and knowledge, Qwen3.5-397B-A17B or DeepSeek-V3.1-Terminus?

Qwen3.5-397B-A17B ranks 73 of 198 models on sale for hard questions across science, maths and general knowledge, against 109 for DeepSeek-V3.1-Terminus.

Which is better for writing, Qwen3.5-397B-A17B or DeepSeek-V3.1-Terminus?

Qwen3.5-397B-A17B ranks 69 of 188 models on sale for what people prefer in blind comparisons, and judged writing quality, against 81 for DeepSeek-V3.1-Terminus.

Which has the bigger context window, Qwen3.5-397B-A17B or DeepSeek-V3.1-Terminus?

Qwen3.5-397B-A17B: 262,144 tokens, against 163,840 for DeepSeek-V3.1-Terminus.

Run Qwen3.5-397B-A17B and DeepSeek-V3.1-Terminus on your own prompt

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