Mercury 2 vs Gemini 3.1 Flash-Lite

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

Mercury 2 is clearly ahead on the aggregate, 65 to 53. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Mercury 2's sharpest advantage is in coding, where it averages 41.1 against 24.7. The single biggest benchmark swing on the page is SWE-bench Verified, 46 to 22. Gemini 3.1 Flash-Lite does hit back in multimodal & grounded, so the answer changes if that is the part of the workload you care about most.

Mercury 2 is also the more expensive model on tokens at $0.25 input / $0.75 output per 1M tokens, versus $0.10 input / $0.40 output per 1M tokens for Gemini 3.1 Flash-Lite. Mercury 2 is the reasoning model in the pair, while Gemini 3.1 Flash-Lite 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 3.1 Flash-Lite gives you the larger context window at 1M, compared with 128K for Mercury 2.

Quick Verdict

Pick Mercury 2 if you want the stronger benchmark profile. Gemini 3.1 Flash-Lite only becomes the better choice if multimodal & grounded is the priority or you want the cheaper token bill.

Agentic

Mercury 2

Mercury 2

63.7

Gemini 3.1 Flash-Lite

49.2

63
Terminal-Bench 2.0
47
67
BrowseComp
60
62
OSWorld-Verified
44

Coding

Mercury 2

Mercury 2

41.1

Gemini 3.1 Flash-Lite

24.7

75
HumanEval
55
46
SWE-bench Verified
22
38
LiveCodeBench
21
43
SWE-bench Pro
29

Multimodal & Grounded

Gemini 3.1 Flash-Lite

Mercury 2

68.3

Gemini 3.1 Flash-Lite

73.1

66
MMMU-Pro
74
71
OfficeQA Pro
72

Reasoning

Mercury 2

Mercury 2

80.1

Gemini 3.1 Flash-Lite

65.8

82
SimpleQA
60
82
MuSR
58
87
BBH
74
77
LongBench v2
69
76
MRCRv2
73

Knowledge

Mercury 2

Mercury 2

57.2

Gemini 3.1 Flash-Lite

45.3

78
MMLU
63
78
GPQA
62
76
SuperGPQA
60
74
OpenBookQA
58
72
MMLU-Pro
63
9
HLE
1
69
FrontierScience
55

Instruction Following

Mercury 2

Mercury 2

84

Gemini 3.1 Flash-Lite

79

84
IFEval
79

Multilingual

Mercury 2

Mercury 2

79.7

Gemini 3.1 Flash-Lite

69.8

81
MGSM
73
79
MMLU-ProX
68

Mathematics

Mercury 2

Mercury 2

80.9

Gemini 3.1 Flash-Lite

66.1

81
AIME 2023
63
83
AIME 2024
65
82
AIME 2025
64
77
HMMT Feb 2023
59
79
HMMT Feb 2024
61
78
HMMT Feb 2025
60
80
BRUMO 2025
62
82
MATH-500
71

Frequently Asked Questions

Which is better, Mercury 2 or Gemini 3.1 Flash-Lite?

Mercury 2 is ahead overall, 65 to 53. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 46 and 22.

Which is better for knowledge tasks, Mercury 2 or Gemini 3.1 Flash-Lite?

Mercury 2 has the edge for knowledge tasks in this comparison, averaging 57.2 versus 45.3. Inside this category, GPQA is the benchmark that creates the most daylight between them.

Which is better for coding, Mercury 2 or Gemini 3.1 Flash-Lite?

Mercury 2 has the edge for coding in this comparison, averaging 41.1 versus 24.7. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, Mercury 2 or Gemini 3.1 Flash-Lite?

Mercury 2 has the edge for math in this comparison, averaging 80.9 versus 66.1. Inside this category, AIME 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, Mercury 2 or Gemini 3.1 Flash-Lite?

Mercury 2 has the edge for reasoning in this comparison, averaging 80.1 versus 65.8. Inside this category, MuSR is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, Mercury 2 or Gemini 3.1 Flash-Lite?

Mercury 2 has the edge for agentic tasks in this comparison, averaging 63.7 versus 49.2. Inside this category, OSWorld-Verified is the benchmark that creates the most daylight between them.

Which is better for multimodal and grounded tasks, Mercury 2 or Gemini 3.1 Flash-Lite?

Gemini 3.1 Flash-Lite has the edge for multimodal and grounded tasks in this comparison, averaging 73.1 versus 68.3. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, Mercury 2 or Gemini 3.1 Flash-Lite?

Mercury 2 has the edge for instruction following in this comparison, averaging 84 versus 79. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, Mercury 2 or Gemini 3.1 Flash-Lite?

Mercury 2 has the edge for multilingual tasks in this comparison, averaging 79.7 versus 69.8. Inside this category, MMLU-ProX 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.