DeepSeek V3.1 (Reasoning) vs Qwen3.5-27B

Side-by-side benchmark comparison across agentic, coding, multimodal, knowledge, reasoning, and math workflows.

Agentic
Coding
Multimodal & Grounded
Reasoning
Knowledge
Instruction Following
Multilingual
Mathematics

DeepSeek V3.1 (Reasoning)· Qwen3.5-27B

Quick Verdict

Pick Qwen3.5-27B if you want the stronger benchmark profile. DeepSeek V3.1 (Reasoning) only becomes the better choice if its workflow or ecosystem matters more than the raw scoreboard.

Qwen3.5-27B is clearly ahead on the aggregate, 71 to 43. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Qwen3.5-27B's sharpest advantage is in coding, where it averages 77.6 against 19. The single biggest benchmark swing on the page is LiveCodeBench, 16% to 80.7%.

Qwen3.5-27B gives you the larger context window at 262K, compared with 128K for DeepSeek V3.1 (Reasoning).

Operational tradeoffs

PriceFree*Free*
SpeedN/AN/A
TTFTN/AN/A
Context128K262K

Decision framing

BenchLM keeps the benchmark table and the operator tradeoffs on the same page so a better score does not hide a materially slower, pricier, or smaller-context model.

Runtime metrics show N/A when BenchLM does not have a sourced snapshot for that exact model. The scoring rules and freshness policy are documented on the methodology page.

BenchmarkDeepSeek V3.1 (Reasoning)Qwen3.5-27B
AgenticQwen3.5-27B wins
Terminal-Bench 2.042%41.6%
BrowseComp48%61%
OSWorld-Verified44%56.2%
tau2-bench79%
CodingQwen3.5-27B wins
HumanEval26%
SWE-bench Verified14%72.4%
LiveCodeBench16%80.7%
SWE-bench Pro25%
Multimodal & GroundedQwen3.5-27B wins
MMMU-Pro37%75%
OfficeQA Pro47%
ReasoningQwen3.5-27B wins
MuSR30%
BBH64%
LongBench v257%60.6%
MRCRv256%
KnowledgeQwen3.5-27B wins
MMLU34%
GPQA33%85.5%
SuperGPQA31%65.6%
MMLU-Pro53%86.1%
HLE10%
FrontierScience37%
SimpleQA32%
Instruction FollowingQwen3.5-27B wins
IFEval70%95%
MultilingualQwen3.5-27B wins
MGSM64%
MMLU-ProX61%82.2%
Mathematics
AIME 202334%
AIME 202436%
AIME 202535%
HMMT Feb 202330%
HMMT Feb 202432%
HMMT Feb 202531%
BRUMO 202533%
MATH-50062%
Frequently Asked Questions (8)

Which is better, DeepSeek V3.1 (Reasoning) or Qwen3.5-27B?

Qwen3.5-27B is ahead overall, 71 to 43. The biggest single separator in this matchup is LiveCodeBench, where the scores are 16% and 80.7%.

Which is better for knowledge tasks, DeepSeek V3.1 (Reasoning) or Qwen3.5-27B?

Qwen3.5-27B has the edge for knowledge tasks in this comparison, averaging 80.6 versus 32.5. Inside this category, GPQA is the benchmark that creates the most daylight between them.

Which is better for coding, DeepSeek V3.1 (Reasoning) or Qwen3.5-27B?

Qwen3.5-27B has the edge for coding in this comparison, averaging 77.6 versus 19. Inside this category, LiveCodeBench is the benchmark that creates the most daylight between them.

Which is better for reasoning, DeepSeek V3.1 (Reasoning) or Qwen3.5-27B?

Qwen3.5-27B has the edge for reasoning in this comparison, averaging 60.6 versus 49.5. Inside this category, LongBench v2 is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, DeepSeek V3.1 (Reasoning) or Qwen3.5-27B?

Qwen3.5-27B has the edge for agentic tasks in this comparison, averaging 51.6 versus 44.2. Inside this category, BrowseComp is the benchmark that creates the most daylight between them.

Which is better for multimodal and grounded tasks, DeepSeek V3.1 (Reasoning) or Qwen3.5-27B?

Qwen3.5-27B has the edge for multimodal and grounded tasks in this comparison, averaging 75 versus 41.5. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, DeepSeek V3.1 (Reasoning) or Qwen3.5-27B?

Qwen3.5-27B has the edge for instruction following in this comparison, averaging 95 versus 70. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, DeepSeek V3.1 (Reasoning) or Qwen3.5-27B?

Qwen3.5-27B has the edge for multilingual tasks in this comparison, averaging 82.2 versus 62.1. Inside this category, MMLU-ProX is the benchmark that creates the most daylight between them.

Last updated: March 31, 2026

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