Grok 4.1 Fast vs o3-mini

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

Grok 4.1 Fast is clearly ahead on the aggregate, 83 to 56. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Grok 4.1 Fast's sharpest advantage is in coding, where it averages 69.3 against 49.3. The single biggest benchmark swing on the page is SWE-bench Verified, 68 to 49.3. o3-mini does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.

o3-mini is the reasoning model in the pair, while Grok 4.1 Fast 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. Grok 4.1 Fast gives you the larger context window at 1M, compared with 200K for o3-mini.

Quick Verdict

Pick Grok 4.1 Fast if you want the stronger benchmark profile. o3-mini only becomes the better choice if knowledge is the priority or you want the stronger reasoning-first profile.

Knowledge

o3-mini

Grok 4.1 Fast

77.5

o3-mini

82.1

94
MMLU
86.9
92
GPQA
77.2
90
SuperGPQA
-
88
OpenBookQA
-
81
MMLU-Pro
-
20
HLE
-

Coding

Grok 4.1 Fast

Grok 4.1 Fast

69.3

o3-mini

49.3

86
HumanEval
-
68
SWE-bench Verified
49.3
54
LiveCodeBench
-

Mathematics

Grok 4.1 Fast

Grok 4.1 Fast

94.3

o3-mini

87.3

96
AIME 2023
-
98
AIME 2024
87.3
97
AIME 2025
-
92
HMMT Feb 2023
-
94
HMMT Feb 2024
-
93
HMMT Feb 2025
-
95
BRUMO 2025
-
89
MATH-500
-

Reasoning

Grok 4.1 Fast
90
SimpleQA
-
88
MuSR
-
87
BBH
-

Instruction Following

o3-mini

Grok 4.1 Fast

90

o3-mini

93.9

90
IFEval
93.9

Multilingual

Grok 4.1 Fast
88
MGSM
-

Frequently Asked Questions

Which is better, Grok 4.1 Fast or o3-mini?

Grok 4.1 Fast is ahead overall, 83 to 56. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 68 and 49.3.

Which is better for knowledge tasks, Grok 4.1 Fast or o3-mini?

o3-mini has the edge for knowledge tasks in this comparison, averaging 82.1 versus 77.5. Inside this category, GPQA is the benchmark that creates the most daylight between them.

Which is better for coding, Grok 4.1 Fast or o3-mini?

Grok 4.1 Fast has the edge for coding in this comparison, averaging 69.3 versus 49.3. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, Grok 4.1 Fast or o3-mini?

Grok 4.1 Fast has the edge for math in this comparison, averaging 94.3 versus 87.3. Inside this category, AIME 2024 is the benchmark that creates the most daylight between them.

Which is better for instruction following, Grok 4.1 Fast or o3-mini?

o3-mini has the edge for instruction following in this comparison, averaging 93.9 versus 90. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Last updated: March 9, 2026

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