Mercury 2 vs Claude 3 Opus

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

Mercury 2 is clearly ahead on the aggregate, 65 to 51. 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 19. The single biggest benchmark swing on the page is SWE-bench Verified, 46 to 10. Claude 3 Opus 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 the reasoning model in the pair, while Claude 3 Opus 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. Claude 3 Opus gives you the larger context window at 200K, compared with 128K for Mercury 2.

Quick Verdict

Pick Mercury 2 if you want the stronger benchmark profile. Claude 3 Opus only becomes the better choice if multimodal & grounded is the priority or you need the larger 200K context window.

Agentic

Mercury 2

Mercury 2

63.7

Claude 3 Opus

48.1

63
Terminal-Bench 2.0
44
67
BrowseComp
56
62
OSWorld-Verified
47

Coding

Mercury 2

Mercury 2

41.1

Claude 3 Opus

19

75
HumanEval
53
46
SWE-bench Verified
10
38
LiveCodeBench
20
43
SWE-bench Pro
20

Multimodal & Grounded

Claude 3 Opus

Mercury 2

68.3

Claude 3 Opus

70.3

66
MMMU-Pro
73
71
OfficeQA Pro
67

Reasoning

Mercury 2

Mercury 2

80.1

Claude 3 Opus

61.6

82
SimpleQA
59
82
MuSR
57
87
BBH
74
77
LongBench v2
62
76
MRCRv2
63

Knowledge

Mercury 2

Mercury 2

57.2

Claude 3 Opus

45

78
MMLU
61
78
GPQA
61
76
SuperGPQA
59
74
OpenBookQA
57
72
MMLU-Pro
62
9
HLE
1
69
FrontierScience
56

Instruction Following

Mercury 2

Mercury 2

84

Claude 3 Opus

77

84
IFEval
77

Multilingual

Mercury 2

Mercury 2

79.7

Claude 3 Opus

69.8

81
MGSM
73
79
MMLU-ProX
68

Mathematics

Mercury 2

Mercury 2

80.9

Claude 3 Opus

65.9

81
AIME 2023
61
83
AIME 2024
63
82
AIME 2025
62
77
HMMT Feb 2023
57
79
HMMT Feb 2024
59
78
HMMT Feb 2025
58
80
BRUMO 2025
60
82
MATH-500
73

Frequently Asked Questions

Which is better, Mercury 2 or Claude 3 Opus?

Mercury 2 is ahead overall, 65 to 51. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 46 and 10.

Which is better for knowledge tasks, Mercury 2 or Claude 3 Opus?

Mercury 2 has the edge for knowledge tasks in this comparison, averaging 57.2 versus 45. Inside this category, MMLU is the benchmark that creates the most daylight between them.

Which is better for coding, Mercury 2 or Claude 3 Opus?

Mercury 2 has the edge for coding in this comparison, averaging 41.1 versus 19. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, Mercury 2 or Claude 3 Opus?

Mercury 2 has the edge for math in this comparison, averaging 80.9 versus 65.9. Inside this category, AIME 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, Mercury 2 or Claude 3 Opus?

Mercury 2 has the edge for reasoning in this comparison, averaging 80.1 versus 61.6. Inside this category, MuSR is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, Mercury 2 or Claude 3 Opus?

Mercury 2 has the edge for agentic tasks in this comparison, averaging 63.7 versus 48.1. 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, Mercury 2 or Claude 3 Opus?

Claude 3 Opus has the edge for multimodal and grounded tasks in this comparison, averaging 70.3 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 Claude 3 Opus?

Mercury 2 has the edge for instruction following in this comparison, averaging 84 versus 77. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, Mercury 2 or Claude 3 Opus?

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

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