GPT-5.3 Instant vs Qwen3.5 397B

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

GPT-5.3 Instant is clearly ahead on the aggregate, 87 to 62. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.3 Instant's sharpest advantage is in coding, where it averages 78.7 against 40.7. The single biggest benchmark swing on the page is SWE-bench Pro, 83 to 42.

GPT-5.3 Instant is also the more expensive model on tokens at $1.75 input / $14.00 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. GPT-5.3 Instant is the reasoning model in the pair, while Qwen3.5 397B is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use.

Quick Verdict

Pick GPT-5.3 Instant if you want the stronger benchmark profile. Qwen3.5 397B only becomes the better choice if you want the cheaper token bill or you would rather avoid the extra latency and token burn of a reasoning model.

Agentic

GPT-5.3 Instant

GPT-5.3 Instant

82.9

Qwen3.5 397B

56.9

86
Terminal-Bench 2.0
58
82
BrowseComp
62
80
OSWorld-Verified
52

Coding

GPT-5.3 Instant

GPT-5.3 Instant

78.7

Qwen3.5 397B

40.7

88
HumanEval
75
76
SWE-bench Verified
42
75
LiveCodeBench
39
83
SWE-bench Pro
42

Multimodal & Grounded

GPT-5.3 Instant

GPT-5.3 Instant

95

Qwen3.5 397B

61.4

95
MMMU-Pro
56
95
OfficeQA Pro
68

Reasoning

GPT-5.3 Instant

GPT-5.3 Instant

94.2

Qwen3.5 397B

75.9

96
SimpleQA
80
94
MuSR
78
97
BBH
82
92
LongBench v2
72
94
MRCRv2
71

Knowledge

GPT-5.3 Instant

GPT-5.3 Instant

80.8

Qwen3.5 397B

59.3

99
MMLU
83
98
GPQA
82
96
SuperGPQA
80
94
OpenBookQA
78
89
MMLU-Pro
73
44
HLE
10
92
FrontierScience
71

Instruction Following

GPT-5.3 Instant

GPT-5.3 Instant

96

Qwen3.5 397B

82

96
IFEval
82

Multilingual

GPT-5.3 Instant

GPT-5.3 Instant

93.4

Qwen3.5 397B

78.8

96
MGSM
82
92
MMLU-ProX
77

Mathematics

GPT-5.3 Instant

GPT-5.3 Instant

97.2

Qwen3.5 397B

81.6

99
AIME 2023
83
99
AIME 2024
85
98
AIME 2025
84
95
HMMT Feb 2023
79
97
HMMT Feb 2024
81
96
HMMT Feb 2025
80
96
BRUMO 2025
82
98
MATH-500
81

Frequently Asked Questions

Which is better, GPT-5.3 Instant or Qwen3.5 397B?

GPT-5.3 Instant is ahead overall, 87 to 62. The biggest single separator in this matchup is SWE-bench Pro, where the scores are 83 and 42.

Which is better for knowledge tasks, GPT-5.3 Instant or Qwen3.5 397B?

GPT-5.3 Instant has the edge for knowledge tasks in this comparison, averaging 80.8 versus 59.3. Inside this category, HLE is the benchmark that creates the most daylight between them.

Which is better for coding, GPT-5.3 Instant or Qwen3.5 397B?

GPT-5.3 Instant has the edge for coding in this comparison, averaging 78.7 versus 40.7. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.

Which is better for math, GPT-5.3 Instant or Qwen3.5 397B?

GPT-5.3 Instant has the edge for math in this comparison, averaging 97.2 versus 81.6. Inside this category, MATH-500 is the benchmark that creates the most daylight between them.

Which is better for reasoning, GPT-5.3 Instant or Qwen3.5 397B?

GPT-5.3 Instant has the edge for reasoning in this comparison, averaging 94.2 versus 75.9. Inside this category, MRCRv2 is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, GPT-5.3 Instant or Qwen3.5 397B?

GPT-5.3 Instant has the edge for agentic tasks in this comparison, averaging 82.9 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, GPT-5.3 Instant or Qwen3.5 397B?

GPT-5.3 Instant has the edge for multimodal and grounded tasks in this comparison, averaging 95 versus 61.4. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, GPT-5.3 Instant or Qwen3.5 397B?

GPT-5.3 Instant has the edge for instruction following in this comparison, averaging 96 versus 82. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, GPT-5.3 Instant or Qwen3.5 397B?

GPT-5.3 Instant has the edge for multilingual tasks in this comparison, averaging 93.4 versus 78.8. Inside this category, MMLU-ProX is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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