Mercury 2 vs GPT-4o

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

Mercury 2 is clearly ahead on the aggregate, 65 to 56. 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 reasoning, where it averages 80.1 against 64.6. The single biggest benchmark swing on the page is SWE-bench Verified, 46 to 20. GPT-4o does hit back in multimodal & grounded, so the answer changes if that is the part of the workload you care about most.

GPT-4o is also the more expensive model on tokens at $2.50 input / $10.00 output per 1M tokens, versus $0.25 input / $0.75 output per 1M tokens for Mercury 2. That is roughly 13.3x on output cost alone. Mercury 2 is the reasoning model in the pair, while GPT-4o 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.

Quick Verdict

Pick Mercury 2 if you want the stronger benchmark profile. GPT-4o only becomes the better choice if multimodal & grounded is the priority or you would rather avoid the extra latency and token burn of a reasoning model.

Agentic

Mercury 2

Mercury 2

63.7

GPT-4o

51.2

63
Terminal-Bench 2.0
49
67
BrowseComp
59
62
OSWorld-Verified
48

Coding

Mercury 2

Mercury 2

41.1

GPT-4o

32.2

75
HumanEval
58
46
SWE-bench Verified
20
38
LiveCodeBench
38
43
SWE-bench Pro
29

Multimodal & Grounded

GPT-4o

Mercury 2

68.3

GPT-4o

72.2

66
MMMU-Pro
74
71
OfficeQA Pro
70

Reasoning

Mercury 2

Mercury 2

80.1

GPT-4o

64.6

82
SimpleQA
64
82
MuSR
62
87
BBH
82
77
LongBench v2
62
76
MRCRv2
63

Knowledge

Mercury 2

Mercury 2

57.2

GPT-4o

47.4

78
MMLU
66
78
GPQA
66
76
SuperGPQA
64
74
OpenBookQA
62
72
MMLU-Pro
64
9
HLE
1
69
FrontierScience
58

Instruction Following

Mercury 2

Mercury 2

84

GPT-4o

82

84
IFEval
82

Multilingual

Mercury 2

Mercury 2

79.7

GPT-4o

75.5

81
MGSM
82
79
MMLU-ProX
72

Mathematics

Mercury 2

Mercury 2

80.9

GPT-4o

71.8

81
AIME 2023
66
83
AIME 2024
68
82
AIME 2025
67
77
HMMT Feb 2023
62
79
HMMT Feb 2024
64
78
HMMT Feb 2025
63
80
BRUMO 2025
65
82
MATH-500
80

Frequently Asked Questions

Which is better, Mercury 2 or GPT-4o?

Mercury 2 is ahead overall, 65 to 56. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 46 and 20.

Which is better for knowledge tasks, Mercury 2 or GPT-4o?

Mercury 2 has the edge for knowledge tasks in this comparison, averaging 57.2 versus 47.4. Inside this category, MMLU is the benchmark that creates the most daylight between them.

Which is better for coding, Mercury 2 or GPT-4o?

Mercury 2 has the edge for coding in this comparison, averaging 41.1 versus 32.2. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, Mercury 2 or GPT-4o?

Mercury 2 has the edge for math in this comparison, averaging 80.9 versus 71.8. Inside this category, AIME 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, Mercury 2 or GPT-4o?

Mercury 2 has the edge for reasoning in this comparison, averaging 80.1 versus 64.6. Inside this category, MuSR is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, Mercury 2 or GPT-4o?

Mercury 2 has the edge for agentic tasks in this comparison, averaging 63.7 versus 51.2. 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 GPT-4o?

GPT-4o has the edge for multimodal and grounded tasks in this comparison, averaging 72.2 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 GPT-4o?

Mercury 2 has the edge for instruction following in this comparison, averaging 84 versus 82. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, Mercury 2 or GPT-4o?

Mercury 2 has the edge for multilingual tasks in this comparison, averaging 79.7 versus 75.5. Inside this category, MMLU-ProX is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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