Compare / Qwen3.5-27B vs Claude Sonnet 4.5

Qwen3.5-27B vs Claude Sonnet 4.5

Which is cheaper, which is more capable, and which does better at each kind of work, from 20 results on 5 sources that measured both models.

AlibabaQwen3.5-27B Released 24 Feb 2026 · $0.27 in · $2.16 out
AnthropicClaude Sonnet 4.5 Released 29 Sep 2025 · $3.00 in · $15.00 out
Qwen3.5-27B wins 7Claude Sonnet 4.5 wins 13

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 9 October 2026 (catalogue release 2026-10-09-dd620e778ac5). See also Alibaba vs Anthropic, every model from both labs.

Qwen3.5-27B or Claude Sonnet 4.5? The short answer

Pick Qwen3.5-27B: it scores higher (Intelligence Index 22.9 against 20.7) and costs less.

  • Qwen3.5-27B is cheaper: $0.74 against $6.00 per million tokens, 8.1 times less.
  • Qwen3.5-27B scores higher on the Artificial Analysis Intelligence Index: 22.9 against 20.7.
  • Qwen3.5-27B is newer: released 24 Feb 2026, against 29 Sep 2025 for Claude Sonnet 4.5.
  • On third-party benchmarks, on the results both models have: Qwen3.5-27B does better for reasoning and knowledge; Claude Sonnet 4.5 for agents and tool use, writing and sticking to the facts.

Head to head

22.9
Intelligence Index
20.7
$0.74
Price per million tokens, blendedlower is better
$6.00
262,144
Context window, tokens
1,000,000

Every fact side by side

Qwen3.5-27BClaude Sonnet 4.5
Price per million tokens$0.27 in · $2.16 out$3.00 in · $15.00 out
Blended (3 in : 1 out)$0.74$6.00
Cheapest host, blended$0.54 (Alibaba)$6.00 (Amazon Bedrock)
Intelligence Index22.920.7
Spring Prompt overall––
Output speed, tokens a second––
Context window262,144 tokens1,000,000 tokens
Released24 Feb 2026 (newer)29 Sep 2025
WeightsOpenClosed
Developer based inChinathe US

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 145 of 164 99 of 164
Professional workReal tasks from banking, consulting and law, business documents and freelance projects not measured 40 of 51
Reasoning and knowledgeHard questions across science, maths and general knowledge 82 of 198 98 of 198
WritingWhat people prefer in blind comparisons, and judged writing quality 98 of 188 34 of 188
Sticking to the factsSummarising without inventing things, and factual answers 121 of 152 101 of 152

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.

MeasureQwen3.5-27BClaude Sonnet 4.5
Arena (formerly LMArena) reported by Arena (formerly LMArena) · 3 results
Overall · TextArena rating, higher is better 129 · 56 of 387 measured 1,409 1,457high-32k reasoning
Overall · Text factualityArena rating, higher is better 112 · 61 of 163 measured 1,420 1,449
Business, management and finance · TextArena rating, higher is better 128 · 51 of 380 measured 1,408 1,461
Artificial Analysis reported by Artificial Analysis · 3 results
Artificial Analysis Intelligence Indexindex score, higher is better 86 · 101 of 243 measured 22.9 20.7thinking reasoning
GPQA Diamond% of questions, higher is better 74 · 94 of 231 measured 85.8% 83.4%thinking reasoning
Humanity's Last Exam% of questions, higher is better 95 · 116 of 242 measured 23.9% 17.8%thinking reasoning
UGI Leaderboard reported by UGI Leaderboard · 3 results
Writing score · UGIscore out of 100, higher is better 99 · 23 of 230 measured 42.4think-prefill reasoning 66.9no reasoning
Requested-length error · UGI% off the requested word count, lower is better 49 · 15 of 230 measured 11.0%think-prefill reasoning 5.0%no reasoning
Style adherence · UGIscore from 0 to 1, higher is better 147 · 8 of 230 measured 0.33no reasoning 0.41thinking reasoning
Vectara Hallucination Leaderboard reported by Vectara Hallucination Leaderboard · 2 results
Hallucination rate · Vectara% of summaries, lower is better 80 · 77 of 104 measured 12.1% 12.0%
Answer rate · Vectara% of documents, higher is better 31 · 86 of 104 measured 99.8% 95.6%
Vending-Bench 2 reported by Vending-Bench 2 · 1 result
Money after a yearUS dollars, higher is better 50 · 34 of 58 measured $201.98 $3,839
Show all 20 results (8 more)
MeasureQwen3.5-27BClaude Sonnet 4.5
Arena (formerly LMArena) reported by Arena (formerly LMArena) · 4 results
Creative writing · TextArena rating, higher is better 145 · 27 of 385 measured 1,358 1,454
Expert prompts · TextArena rating, higher is better 112 · 43 of 338 measured 1,441 1,498high-32k reasoning
Instruction following · TextArena rating, higher is better 122 · 38 of 387 measured 1,401 1,464high-32k reasoning
Writing, literature and language · TextArena rating, higher is better 135 · 38 of 386 measured 1,380 1,454
Artificial Analysis reported by Artificial Analysis · 4 results
IFBench% of instructions, higher is better 24 · 85 of 195 measured 75.6% 57.3%thinking reasoning
Long-context reasoning (AA-LCR)% of questions, higher is better 63 · 96 of 233 measured 77.7% 72.3%thinking reasoning
Terminal-Bench Hard% of tasks, higher is better 61 · 47 of 190 measured 32.6% 35.6%thinking reasoning
τ²-bench telecom% of tasks, higher is better 28 · 73 of 193 measured 93.9% 78.1%thinking reasoning

Quick answers

Is Qwen3.5-27B better than Claude Sonnet 4.5?

Pick Qwen3.5-27B: it scores higher (Intelligence Index 22.9 against 20.7) and costs less.

Which is cheaper, Qwen3.5-27B or Claude Sonnet 4.5?

Qwen3.5-27B is cheaper: $0.74 against $6.00 per million tokens, 8.1 times less.

Which is better for agents and tool use, Qwen3.5-27B or Claude Sonnet 4.5?

Claude Sonnet 4.5 ranks 99 of 164 models on sale for multi-step tasks with tools: support desks, coding agents, function calls, against 145 for Qwen3.5-27B.

Which is better for reasoning and knowledge, Qwen3.5-27B or Claude Sonnet 4.5?

Qwen3.5-27B ranks 82 of 198 models on sale for hard questions across science, maths and general knowledge, against 98 for Claude Sonnet 4.5.

Which is better for writing, Qwen3.5-27B or Claude Sonnet 4.5?

Claude Sonnet 4.5 ranks 34 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 Claude Sonnet 4.5?

Claude Sonnet 4.5 ranks 101 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 Claude Sonnet 4.5?

Claude Sonnet 4.5: 1,000,000 tokens, against 262,144 for Qwen3.5-27B.

Run Qwen3.5-27B and Claude Sonnet 4.5 on your own prompt

Benchmarks aren't your data. Try both side by side in the playground, with the cost of every answer.

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