o3-mini vs Z-1

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

o3-mini is clearly ahead on the aggregate, 56 to 51. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

o3-mini's sharpest advantage is in knowledge, where it averages 82.1 against 44.8. The single biggest benchmark swing on the page is MMLU, 86.9 to 52.

o3-mini is the reasoning model in the pair, while Z-1 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. o3-mini gives you the larger context window at 200K, compared with 128K for Z-1.

Quick Verdict

Pick o3-mini if you want the stronger benchmark profile. Z-1 only becomes the better choice if you would rather avoid the extra latency and token burn of a reasoning model.

Knowledge

o3-mini

o3-mini

82.1

Z-1

44.8

86.9
MMLU
52
77.2
GPQA
51
-
SuperGPQA
49
-
OpenBookQA
47
-
MMLU-Pro
64
-
HLE
6

Coding

o3-mini

o3-mini

49.3

Z-1

33

49.3
SWE-bench Verified
33
-
HumanEval
44
-
LiveCodeBench
22

Mathematics

o3-mini

o3-mini

87.3

Z-1

53.8

87.3
AIME 2024
54
-
AIME 2023
52
-
AIME 2025
53
-
HMMT Feb 2023
48
-
HMMT Feb 2024
50
-
HMMT Feb 2025
49
-
BRUMO 2025
51
-
MATH-500
73

Reasoning

Z-1
-
SimpleQA
50
-
MuSR
48
-
BBH
74

Instruction Following

o3-mini

o3-mini

93.9

Z-1

80

93.9
IFEval
80

Multilingual

Z-1
-
MGSM
74

Frequently Asked Questions

Which is better, o3-mini or Z-1?

o3-mini is ahead overall, 56 to 51. The biggest single separator in this matchup is MMLU, where the scores are 86.9 and 52.

Which is better for knowledge tasks, o3-mini or Z-1?

o3-mini has the edge for knowledge tasks in this comparison, averaging 82.1 versus 44.8. Inside this category, MMLU is the benchmark that creates the most daylight between them.

Which is better for coding, o3-mini or Z-1?

o3-mini has the edge for coding in this comparison, averaging 49.3 versus 33. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, o3-mini or Z-1?

o3-mini has the edge for math in this comparison, averaging 87.3 versus 53.8. Inside this category, AIME 2024 is the benchmark that creates the most daylight between them.

Which is better for instruction following, o3-mini or Z-1?

o3-mini has the edge for instruction following in this comparison, averaging 93.9 versus 80. 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.