Step 3.5 Flash vs Qwen3.5 397B

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

Step 3.5 Flash is clearly ahead on the aggregate, 66 to 62. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Step 3.5 Flash's sharpest advantage is in coding, where it averages 47.1 against 40.7. The single biggest benchmark swing on the page is MMMU-Pro, 64 to 56.

Step 3.5 Flash is also the more expensive model on tokens at $0.10 input / $0.30 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for Qwen3.5 397B. That is roughly Infinityx on output cost alone. Step 3.5 Flash gives you the larger context window at 256K, compared with 128K for Qwen3.5 397B.

Quick Verdict

Pick Step 3.5 Flash if you want the stronger benchmark profile. Qwen3.5 397B only becomes the better choice if you want the cheaper token bill.

Agentic

Step 3.5 Flash

Step 3.5 Flash

60.2

Qwen3.5 397B

56.9

62
Terminal-Bench 2.0
58
66
BrowseComp
62
54
OSWorld-Verified
52

Coding

Step 3.5 Flash

Step 3.5 Flash

47.1

Qwen3.5 397B

40.7

77
HumanEval
75
48
SWE-bench Verified
42
45
LiveCodeBench
39
49
SWE-bench Pro
42

Multimodal & Grounded

Step 3.5 Flash

Step 3.5 Flash

66.7

Qwen3.5 397B

61.4

64
MMMU-Pro
56
70
OfficeQA Pro
68

Reasoning

Step 3.5 Flash

Step 3.5 Flash

78.3

Qwen3.5 397B

75.9

82
SimpleQA
80
82
MuSR
78
83
BBH
82
74
LongBench v2
72
73
MRCRv2
71

Knowledge

Step 3.5 Flash

Step 3.5 Flash

60.8

Qwen3.5 397B

59.3

84
MMLU
83
83
GPQA
82
81
SuperGPQA
80
79
OpenBookQA
78
76
MMLU-Pro
73
12
HLE
10
71
FrontierScience
71

Instruction Following

Step 3.5 Flash

Step 3.5 Flash

87

Qwen3.5 397B

82

87
IFEval
82

Multilingual

Step 3.5 Flash

Step 3.5 Flash

82.8

Qwen3.5 397B

78.8

86
MGSM
82
81
MMLU-ProX
77

Mathematics

Step 3.5 Flash

Step 3.5 Flash

84.5

Qwen3.5 397B

81.6

85
AIME 2023
83
87
AIME 2024
85
86
AIME 2025
84
81
HMMT Feb 2023
79
83
HMMT Feb 2024
81
82
HMMT Feb 2025
80
84
BRUMO 2025
82
85
MATH-500
81

Frequently Asked Questions

Which is better, Step 3.5 Flash or Qwen3.5 397B?

Step 3.5 Flash is ahead overall, 66 to 62. The biggest single separator in this matchup is MMMU-Pro, where the scores are 64 and 56.

Which is better for knowledge tasks, Step 3.5 Flash or Qwen3.5 397B?

Step 3.5 Flash has the edge for knowledge tasks in this comparison, averaging 60.8 versus 59.3. Inside this category, MMLU-Pro is the benchmark that creates the most daylight between them.

Which is better for coding, Step 3.5 Flash or Qwen3.5 397B?

Step 3.5 Flash has the edge for coding in this comparison, averaging 47.1 versus 40.7. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.

Which is better for math, Step 3.5 Flash or Qwen3.5 397B?

Step 3.5 Flash has the edge for math in this comparison, averaging 84.5 versus 81.6. Inside this category, MATH-500 is the benchmark that creates the most daylight between them.

Which is better for reasoning, Step 3.5 Flash or Qwen3.5 397B?

Step 3.5 Flash has the edge for reasoning in this comparison, averaging 78.3 versus 75.9. Inside this category, MuSR is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, Step 3.5 Flash or Qwen3.5 397B?

Step 3.5 Flash has the edge for agentic tasks in this comparison, averaging 60.2 versus 56.9. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.

Which is better for multimodal and grounded tasks, Step 3.5 Flash or Qwen3.5 397B?

Step 3.5 Flash has the edge for multimodal and grounded tasks in this comparison, averaging 66.7 versus 61.4. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, Step 3.5 Flash or Qwen3.5 397B?

Step 3.5 Flash has the edge for instruction following in this comparison, averaging 87 versus 82. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, Step 3.5 Flash or Qwen3.5 397B?

Step 3.5 Flash has the edge for multilingual tasks in this comparison, averaging 82.8 versus 78.8. Inside this category, MGSM is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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