Seed 1.6 vs Gemini 2.5 Flash

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

Seed 1.6 is clearly ahead on the aggregate, 65 to 49. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Seed 1.6's sharpest advantage is in coding, where it averages 42.4 against 21.7. The single biggest benchmark swing on the page is SWE-bench Verified, 46 to 23.

Seed 1.6 is also the more expensive model on tokens at $0.25 input / $2.00 output per 1M tokens, versus $0.15 input / $0.60 output per 1M tokens for Gemini 2.5 Flash. That is roughly 3.3x on output cost alone. Seed 1.6 is the reasoning model in the pair, while Gemini 2.5 Flash 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. Gemini 2.5 Flash gives you the larger context window at 1M, compared with 256K for Seed 1.6.

Quick Verdict

Pick Seed 1.6 if you want the stronger benchmark profile. Gemini 2.5 Flash only becomes the better choice if you want the cheaper token bill or you need the larger 1M context window.

Agentic

Seed 1.6

Seed 1.6

62.3

Gemini 2.5 Flash

46.5

63
Terminal-Bench 2.0
44
67
BrowseComp
58
58
OSWorld-Verified
41

Coding

Seed 1.6

Seed 1.6

42.4

Gemini 2.5 Flash

21.7

64
HumanEval
42
46
SWE-bench Verified
23
38
LiveCodeBench
18
46
SWE-bench Pro
25

Multimodal & Grounded

Seed 1.6

Seed 1.6

79.6

Gemini 2.5 Flash

67.7

80
MMMU-Pro
69
79
OfficeQA Pro
66

Reasoning

Seed 1.6

Seed 1.6

74.5

Gemini 2.5 Flash

59.2

69
SimpleQA
48
69
MuSR
46
86
BBH
75
77
LongBench v2
68
78
MRCRv2
68

Knowledge

Seed 1.6

Seed 1.6

56.4

Gemini 2.5 Flash

40.5

73
MMLU
50
72
GPQA
49
70
SuperGPQA
47
68
OpenBookQA
45
75
MMLU-Pro
64
11
HLE
1
68
FrontierScience
49

Instruction Following

Seed 1.6

Seed 1.6

87

Gemini 2.5 Flash

79

87
IFEval
79

Multilingual

Seed 1.6

Seed 1.6

83.4

Gemini 2.5 Flash

70.8

88
MGSM
74
81
MMLU-ProX
69

Mathematics

Seed 1.6

Seed 1.6

75.9

Gemini 2.5 Flash

59.4

72
AIME 2023
50
74
AIME 2024
52
73
AIME 2025
51
68
HMMT Feb 2023
46
70
HMMT Feb 2024
48
69
HMMT Feb 2025
47
71
BRUMO 2025
49
82
MATH-500
72

Frequently Asked Questions

Which is better, Seed 1.6 or Gemini 2.5 Flash?

Seed 1.6 is ahead overall, 65 to 49. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 46 and 23.

Which is better for knowledge tasks, Seed 1.6 or Gemini 2.5 Flash?

Seed 1.6 has the edge for knowledge tasks in this comparison, averaging 56.4 versus 40.5. Inside this category, MMLU is the benchmark that creates the most daylight between them.

Which is better for coding, Seed 1.6 or Gemini 2.5 Flash?

Seed 1.6 has the edge for coding in this comparison, averaging 42.4 versus 21.7. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, Seed 1.6 or Gemini 2.5 Flash?

Seed 1.6 has the edge for math in this comparison, averaging 75.9 versus 59.4. Inside this category, AIME 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, Seed 1.6 or Gemini 2.5 Flash?

Seed 1.6 has the edge for reasoning in this comparison, averaging 74.5 versus 59.2. Inside this category, MuSR is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, Seed 1.6 or Gemini 2.5 Flash?

Seed 1.6 has the edge for agentic tasks in this comparison, averaging 62.3 versus 46.5. 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, Seed 1.6 or Gemini 2.5 Flash?

Seed 1.6 has the edge for multimodal and grounded tasks in this comparison, averaging 79.6 versus 67.7. Inside this category, OfficeQA Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, Seed 1.6 or Gemini 2.5 Flash?

Seed 1.6 has the edge for instruction following in this comparison, averaging 87 versus 79. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, Seed 1.6 or Gemini 2.5 Flash?

Seed 1.6 has the edge for multilingual tasks in this comparison, averaging 83.4 versus 70.8. Inside this category, MGSM is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

Weekly LLM Benchmark Digest

Get notified when new models drop, benchmark scores change, or the leaderboard shifts. One email per week.

Free. No spam. Unsubscribe anytime. We only store derived location metadata for consent routing.