Gemini 3 Pro Deep Think vs o3-mini

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

Gemini 3 Pro Deep Think is clearly ahead on the aggregate, 85 to 56. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Gemini 3 Pro Deep Think's sharpest advantage is in coding, where it averages 69 against 49.3. The single biggest benchmark swing on the page is GPQA, 97 to 77.2. o3-mini does hit back in instruction following, so the answer changes if that is the part of the workload you care about most.

Gemini 3 Pro Deep Think gives you the larger context window at 2M, compared with 200K for o3-mini.

Quick Verdict

Pick Gemini 3 Pro Deep Think if you want the stronger benchmark profile. o3-mini only becomes the better choice if instruction following is the priority.

Knowledge

Gemini 3 Pro Deep Think

Gemini 3 Pro Deep Think

82.8

o3-mini

82.1

99
MMLU
86.9
97
GPQA
77.2
95
SuperGPQA
-
93
OpenBookQA
-
81
MMLU-Pro
-
32
HLE
-

Coding

Gemini 3 Pro Deep Think

Gemini 3 Pro Deep Think

69

o3-mini

49.3

91
HumanEval
-
58
SWE-bench Verified
49.3
58
LiveCodeBench
-

Mathematics

Gemini 3 Pro Deep Think

Gemini 3 Pro Deep Think

96.5

o3-mini

87.3

99
AIME 2023
-
99
AIME 2024
87.3
98
AIME 2025
-
95
HMMT Feb 2023
-
97
HMMT Feb 2024
-
96
HMMT Feb 2025
-
96
BRUMO 2025
-
92
MATH-500
-

Reasoning

Gemini 3 Pro Deep Think
95
SimpleQA
-
93
MuSR
-
95
BBH
-

Instruction Following

o3-mini

Gemini 3 Pro Deep Think

89

o3-mini

93.9

89
IFEval
93.9

Multilingual

Gemini 3 Pro Deep Think
92
MGSM
-

Frequently Asked Questions

Which is better, Gemini 3 Pro Deep Think or o3-mini?

Gemini 3 Pro Deep Think is ahead overall, 85 to 56. The biggest single separator in this matchup is GPQA, where the scores are 97 and 77.2.

Which is better for knowledge tasks, Gemini 3 Pro Deep Think or o3-mini?

Gemini 3 Pro Deep Think has the edge for knowledge tasks in this comparison, averaging 82.8 versus 82.1. Inside this category, GPQA is the benchmark that creates the most daylight between them.

Which is better for coding, Gemini 3 Pro Deep Think or o3-mini?

Gemini 3 Pro Deep Think has the edge for coding in this comparison, averaging 69 versus 49.3. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, Gemini 3 Pro Deep Think or o3-mini?

Gemini 3 Pro Deep Think has the edge for math in this comparison, averaging 96.5 versus 87.3. Inside this category, AIME 2024 is the benchmark that creates the most daylight between them.

Which is better for instruction following, Gemini 3 Pro Deep Think or o3-mini?

o3-mini has the edge for instruction following in this comparison, averaging 93.9 versus 89. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Last updated: March 9, 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.