GPT-5.2 Pro vs Seed 1.6 Flash

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

GPT-5.2 Pro is clearly ahead on the aggregate, 90 to 56. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.2 Pro's sharpest advantage is in coding, where it averages 84.8 against 27.6. The single biggest benchmark swing on the page is SWE-bench Verified, 83 to 24.

GPT-5.2 Pro is also the more expensive model on tokens at $25.00 input / $150.00 output per 1M tokens, versus $0.08 input / $0.30 output per 1M tokens for Seed 1.6 Flash. That is roughly 500.0x on output cost alone. GPT-5.2 Pro gives you the larger context window at 400K, compared with 256K for Seed 1.6 Flash.

Quick Verdict

Pick GPT-5.2 Pro if you want the stronger benchmark profile. Seed 1.6 Flash only becomes the better choice if you want the cheaper token bill.

Agentic

GPT-5.2 Pro

GPT-5.2 Pro

85.9

Seed 1.6 Flash

54.5

88
Terminal-Bench 2.0
52
88
BrowseComp
62
82
OSWorld-Verified
52

Coding

GPT-5.2 Pro

GPT-5.2 Pro

84.8

Seed 1.6 Flash

27.6

93
HumanEval
59
83
SWE-bench Verified
24
81
LiveCodeBench
25
89
SWE-bench Pro
31

Multimodal & Grounded

GPT-5.2 Pro

GPT-5.2 Pro

96

Seed 1.6 Flash

73.1

96
MMMU-Pro
74
96
OfficeQA Pro
72

Reasoning

GPT-5.2 Pro

GPT-5.2 Pro

95.2

Seed 1.6 Flash

66.8

97
SimpleQA
61
95
MuSR
59
98
BBH
75
93
LongBench v2
70
95
MRCRv2
74

Knowledge

GPT-5.2 Pro

GPT-5.2 Pro

81.5

Seed 1.6 Flash

47.3

99
MMLU
65
99
GPQA
64
97
SuperGPQA
62
95
OpenBookQA
60
90
MMLU-Pro
65
44
HLE
3
93
FrontierScience
57

Instruction Following

GPT-5.2 Pro

GPT-5.2 Pro

95

Seed 1.6 Flash

81

95
IFEval
81

Multilingual

GPT-5.2 Pro

GPT-5.2 Pro

93.4

Seed 1.6 Flash

72.8

96
MGSM
76
92
MMLU-ProX
71

Mathematics

GPT-5.2 Pro

GPT-5.2 Pro

98.2

Seed 1.6 Flash

67.1

99
AIME 2023
64
99
AIME 2024
66
99
AIME 2025
65
96
HMMT Feb 2023
60
98
HMMT Feb 2024
62
97
HMMT Feb 2025
61
97
BRUMO 2025
63
99
MATH-500
72

Frequently Asked Questions

Which is better, GPT-5.2 Pro or Seed 1.6 Flash?

GPT-5.2 Pro is ahead overall, 90 to 56. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 83 and 24.

Which is better for knowledge tasks, GPT-5.2 Pro or Seed 1.6 Flash?

GPT-5.2 Pro has the edge for knowledge tasks in this comparison, averaging 81.5 versus 47.3. Inside this category, HLE is the benchmark that creates the most daylight between them.

Which is better for coding, GPT-5.2 Pro or Seed 1.6 Flash?

GPT-5.2 Pro has the edge for coding in this comparison, averaging 84.8 versus 27.6. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, GPT-5.2 Pro or Seed 1.6 Flash?

GPT-5.2 Pro has the edge for math in this comparison, averaging 98.2 versus 67.1. Inside this category, HMMT Feb 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, GPT-5.2 Pro or Seed 1.6 Flash?

GPT-5.2 Pro has the edge for reasoning in this comparison, averaging 95.2 versus 66.8. Inside this category, SimpleQA is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, GPT-5.2 Pro or Seed 1.6 Flash?

GPT-5.2 Pro has the edge for agentic tasks in this comparison, averaging 85.9 versus 54.5. 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-5.2 Pro or Seed 1.6 Flash?

GPT-5.2 Pro has the edge for multimodal and grounded tasks in this comparison, averaging 96 versus 73.1. Inside this category, OfficeQA Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, GPT-5.2 Pro or Seed 1.6 Flash?

GPT-5.2 Pro has the edge for instruction following in this comparison, averaging 95 versus 81. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, GPT-5.2 Pro or Seed 1.6 Flash?

GPT-5.2 Pro has the edge for multilingual tasks in this comparison, averaging 93.4 versus 72.8. Inside this category, MMLU-ProX is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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