Compare / Qwen3.5-27B vs DeepSeek-V3.1
Qwen3.5-27B vs DeepSeek-V3.1
Which is cheaper, which is more capable, and which does better at each kind of work, from 18 results on 4 sources that measured both models.
Of the 18 results both models have, the better value on each. Results whose reported ranges overlap are too close to call.
Results as of 9 October 2026 (catalogue release 2026-10-09-dd620e778ac5). See also Alibaba vs DeepSeek, every model from both labs.
Qwen3.5-27B or DeepSeek-V3.1? The short answer
Pick Qwen3.5-27B: it scores higher (Intelligence Index 22.9 against 13.7) at about the same price.
- They cost about the same: $0.74 and $0.82 per million tokens (three input to one output).
- Qwen3.5-27B scores higher on the Artificial Analysis Intelligence Index: 22.9 against 13.7.
- Qwen3.5-27B is newer: released 24 Feb 2026, against 21 Aug 2025 for DeepSeek-V3.1.
- On third-party benchmarks, on the results both models have: Qwen3.5-27B does better for reasoning and knowledge; DeepSeek-V3.1 for writing and sticking to the facts.
Head to head
Every fact side by side
| Qwen3.5-27B | DeepSeek-V3.1 | |
|---|---|---|
| Price per million tokens | $0.27 in · $2.16 out | $0.55 in · $1.65 out |
| Blended (3 in : 1 out) | $0.74 | $0.82 |
| Cheapest host, blended | $0.54 (Alibaba) | $0.42 (DeepInfra, FP4) |
| Intelligence Index | 22.9 | 13.7 |
| Spring Prompt overall | – | – |
| Output speed, tokens a second | – | – |
| Context window | 262,144 tokens | 163,840 tokens |
| Released | 24 Feb 2026 (newer) | 21 Aug 2025 |
| Weights | Open | Open |
| Developer based in | China | China |
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.
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.
| Measure | Qwen3.5-27B | DeepSeek-V3.1 |
|---|---|---|
| Arena (formerly LMArena) reported by Arena (formerly LMArena) · 3 results | ||
| Overall · TextArena rating, higher is better 129 · 116 of 387 measured | 1,409 | 1,417 |
| Business, management and finance · TextArena rating, higher is better 128 · 112 of 380 measured | 1,408 | 1,417thinking reasoning |
| Creative writing · TextArena rating, higher is better 145 · 91 of 385 measured | 1,358 | 1,402thinking reasoning |
| Artificial Analysis reported by Artificial Analysis · 3 results | ||
| Artificial Analysis Intelligence Indexindex score, higher is better 86 · 137 of 243 measured | 22.9 | 13.7no reasoning |
| GPQA Diamond% of questions, higher is better 74 · 121 of 231 measured | 85.8% | 77.9%thinking reasoning |
| Humanity's Last Exam% of questions, higher is better 95 · 130 of 242 measured | 23.9% | 14.3%thinking reasoning |
| UGI Leaderboard reported by UGI Leaderboard · 3 results | ||
| Writing score · UGIscore out of 100, higher is better 99 · 73 of 230 measured | 42.4think-prefill reasoning | 51.9thinking reasoning |
| Requested-length error · UGI% off the requested word count, lower is better 49 · 166 of 230 measured | 11.0%think-prefill reasoning | 30.0%no reasoning |
| Style adherence · UGIscore from 0 to 1, higher is better 147 · 66 of 230 measured | 0.33no reasoning | 0.36thinking reasoning |
| Vectara Hallucination Leaderboard reported by Vectara Hallucination Leaderboard · 2 results | ||
| Hallucination rate · Vectara% of summaries, lower is better 80 · 18 of 104 measured | 12.1% | 5.5% |
| Answer rate · Vectara% of documents, higher is better 31 · 89 of 104 measured | 99.8% | 94.5% |
Show all 18 results (7 more)
| Measure | Qwen3.5-27B | DeepSeek-V3.1 |
|---|---|---|
| Arena (formerly LMArena) reported by Arena (formerly LMArena) · 3 results | ||
| Expert prompts · TextArena rating, higher is better 112 · 122 of 338 measured | 1,441 | 1,432thinking reasoning |
| Instruction following · TextArena rating, higher is better 122 · 97 of 387 measured | 1,401 | 1,416thinking reasoning |
| Writing, literature and language · TextArena rating, higher is better 135 · 94 of 386 measured | 1,380 | 1,407thinking reasoning |
| Artificial Analysis reported by Artificial Analysis · 4 results | ||
| IFBench% of instructions, higher is better 24 · 127 of 195 measured | 75.6% | 41.5%thinking reasoning |
| Long-context reasoning (AA-LCR)% of questions, higher is better 63 · 141 of 233 measured | 77.7% | 56.7%thinking reasoning |
| Terminal-Bench Hard% of tasks, higher is better 61 · 78 of 190 measured | 32.6% | 25.0%thinking reasoning |
| τ²-bench telecom% of tasks, higher is better 28 · 117 of 193 measured | 93.9% | 37.4%thinking reasoning |
Compare them with other models
Quick answers
Is Qwen3.5-27B better than DeepSeek-V3.1?
Pick Qwen3.5-27B: it scores higher (Intelligence Index 22.9 against 13.7) at about the same price.
Which is cheaper, Qwen3.5-27B or DeepSeek-V3.1?
They cost about the same: $0.74 and $0.82 per million tokens (three input to one output).
Which is better for reasoning and knowledge, Qwen3.5-27B or DeepSeek-V3.1?
Qwen3.5-27B ranks 82 of 198 models on sale for hard questions across science, maths and general knowledge, against 118 for DeepSeek-V3.1.
Which is better for writing, Qwen3.5-27B or DeepSeek-V3.1?
DeepSeek-V3.1 ranks 84 of 188 models on sale for what people prefer in blind comparisons, and judged writing quality, against 98 for Qwen3.5-27B.
Which is better for sticking to the facts, Qwen3.5-27B or DeepSeek-V3.1?
DeepSeek-V3.1 ranks 20 of 152 models on sale for summarising without inventing things, and factual answers, against 121 for Qwen3.5-27B.
Which has the bigger context window, Qwen3.5-27B or DeepSeek-V3.1?
Qwen3.5-27B: 262,144 tokens, against 163,840 for DeepSeek-V3.1.
Run Qwen3.5-27B and DeepSeek-V3.1 on your own prompt
Benchmarks aren't your data. Try both side by side in the playground, with the cost of every answer.