o1-preview vs Seed 1.6 Flash

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

o1-preview is clearly ahead on the aggregate, 77 to 56. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

o1-preview's sharpest advantage is in coding, where it averages 64.6 against 27.6. The single biggest benchmark swing on the page is SWE-bench Verified, 65 to 24.

Seed 1.6 Flash gives you the larger context window at 256K, compared with 200K for o1-preview.

Quick Verdict

Pick o1-preview if you want the stronger benchmark profile. Seed 1.6 Flash only becomes the better choice if you need the larger 256K context window.

Agentic

o1-preview

o1-preview

75.4

Seed 1.6 Flash

54.5

77
Terminal-Bench 2.0
52
79
BrowseComp
62
71
OSWorld-Verified
52

Coding

o1-preview

o1-preview

64.6

Seed 1.6 Flash

27.6

86
HumanEval
59
65
SWE-bench Verified
24
60
LiveCodeBench
25
69
SWE-bench Pro
31

Multimodal & Grounded

o1-preview

o1-preview

75.6

Seed 1.6 Flash

73.1

72
MMMU-Pro
74
80
OfficeQA Pro
72

Reasoning

o1-preview

o1-preview

86.8

Seed 1.6 Flash

66.8

88
SimpleQA
61
86
MuSR
59
93
BBH
75
87
LongBench v2
70
83
MRCRv2
74

Knowledge

o1-preview

o1-preview

71.3

Seed 1.6 Flash

47.3

92
MMLU
65
90
GPQA
64
88
SuperGPQA
62
86
OpenBookQA
60
80
MMLU-Pro
65
32
HLE
3
83
FrontierScience
57

Instruction Following

o1-preview

o1-preview

88

Seed 1.6 Flash

81

88
IFEval
81

Multilingual

o1-preview

o1-preview

87.4

Seed 1.6 Flash

72.8

90
MGSM
76
86
MMLU-ProX
71

Mathematics

o1-preview

o1-preview

93.5

Seed 1.6 Flash

67.1

94
AIME 2023
64
96
AIME 2024
66
95
AIME 2025
65
90
HMMT Feb 2023
60
92
HMMT Feb 2024
62
91
HMMT Feb 2025
61
93
BRUMO 2025
63
94
MATH-500
72

Frequently Asked Questions

Which is better, o1-preview or Seed 1.6 Flash?

o1-preview is ahead overall, 77 to 56. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 65 and 24.

Which is better for knowledge tasks, o1-preview or Seed 1.6 Flash?

o1-preview has the edge for knowledge tasks in this comparison, averaging 71.3 versus 47.3. Inside this category, HLE is the benchmark that creates the most daylight between them.

Which is better for coding, o1-preview or Seed 1.6 Flash?

o1-preview has the edge for coding in this comparison, averaging 64.6 versus 27.6. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, o1-preview or Seed 1.6 Flash?

o1-preview has the edge for math in this comparison, averaging 93.5 versus 67.1. Inside this category, AIME 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, o1-preview or Seed 1.6 Flash?

o1-preview has the edge for reasoning in this comparison, averaging 86.8 versus 66.8. Inside this category, SimpleQA is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, o1-preview or Seed 1.6 Flash?

o1-preview has the edge for agentic tasks in this comparison, averaging 75.4 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, o1-preview or Seed 1.6 Flash?

o1-preview has the edge for multimodal and grounded tasks in this comparison, averaging 75.6 versus 73.1. Inside this category, OfficeQA Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, o1-preview or Seed 1.6 Flash?

o1-preview has the edge for instruction following in this comparison, averaging 88 versus 81. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, o1-preview or Seed 1.6 Flash?

o1-preview has the edge for multilingual tasks in this comparison, averaging 87.4 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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