o3 vs LFM2.5-1.2B-Thinking

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

o3 is clearly ahead on the aggregate, 70 to 33. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

o3's sharpest advantage is in mathematics, where it averages 87.5 against 42.3. The single biggest benchmark swing on the page is HumanEval, 78 to 17.

o3 is also the more expensive model on tokens at $10.00 input / $40.00 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for LFM2.5-1.2B-Thinking. That is roughly Infinityx on output cost alone. o3 gives you the larger context window at 200K, compared with 32K for LFM2.5-1.2B-Thinking.

Quick Verdict

Pick o3 if you want the stronger benchmark profile. LFM2.5-1.2B-Thinking only becomes the better choice if you want the cheaper token bill.

Agentic

o3

o3

69.9

LFM2.5-1.2B-Thinking

34.1

71
Terminal-Bench 2.0
34
75
BrowseComp
37
65
OSWorld-Verified
32

Coding

o3

o3

49.1

LFM2.5-1.2B-Thinking

8.2

78
HumanEval
17
50
SWE-bench Verified
10
40
LiveCodeBench
9
58
SWE-bench Pro
7

Multimodal & Grounded

o3

o3

72.3

LFM2.5-1.2B-Thinking

32.4

70
MMMU-Pro
27
75
OfficeQA Pro
39

Reasoning

o3

o3

82.6

LFM2.5-1.2B-Thinking

38.4

84
SimpleQA
29
82
MuSR
31
86
BBH
67
82
LongBench v2
39
81
MRCRv2
42

Knowledge

o3

o3

66

LFM2.5-1.2B-Thinking

27

86
MMLU
27
87
GPQA
26
85
SuperGPQA
24
83
OpenBookQA
22
75
MMLU-Pro
51
24
HLE
2
77
FrontierScience
31

Instruction Following

o3

o3

85

LFM2.5-1.2B-Thinking

72

85
IFEval
72

Multilingual

o3

o3

81.1

LFM2.5-1.2B-Thinking

60.7

83
MGSM
62
80
MMLU-ProX
60

Mathematics

o3

o3

87.5

LFM2.5-1.2B-Thinking

42.3

88
AIME 2023
28
90
AIME 2024
30
89
AIME 2025
29
84
HMMT Feb 2023
24
86
HMMT Feb 2024
26
85
HMMT Feb 2025
25
87
BRUMO 2025
27
88
MATH-500
61

Frequently Asked Questions

Which is better, o3 or LFM2.5-1.2B-Thinking?

o3 is ahead overall, 70 to 33. The biggest single separator in this matchup is HumanEval, where the scores are 78 and 17.

Which is better for knowledge tasks, o3 or LFM2.5-1.2B-Thinking?

o3 has the edge for knowledge tasks in this comparison, averaging 66 versus 27. Inside this category, GPQA is the benchmark that creates the most daylight between them.

Which is better for coding, o3 or LFM2.5-1.2B-Thinking?

o3 has the edge for coding in this comparison, averaging 49.1 versus 8.2. Inside this category, HumanEval is the benchmark that creates the most daylight between them.

Which is better for math, o3 or LFM2.5-1.2B-Thinking?

o3 has the edge for math in this comparison, averaging 87.5 versus 42.3. Inside this category, AIME 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, o3 or LFM2.5-1.2B-Thinking?

o3 has the edge for reasoning in this comparison, averaging 82.6 versus 38.4. Inside this category, SimpleQA is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, o3 or LFM2.5-1.2B-Thinking?

o3 has the edge for agentic tasks in this comparison, averaging 69.9 versus 34.1. Inside this category, BrowseComp is the benchmark that creates the most daylight between them.

Which is better for multimodal and grounded tasks, o3 or LFM2.5-1.2B-Thinking?

o3 has the edge for multimodal and grounded tasks in this comparison, averaging 72.3 versus 32.4. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, o3 or LFM2.5-1.2B-Thinking?

o3 has the edge for instruction following in this comparison, averaging 85 versus 72. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, o3 or LFM2.5-1.2B-Thinking?

o3 has the edge for multilingual tasks in this comparison, averaging 81.1 versus 60.7. Inside this category, MGSM is the benchmark that creates the most daylight between them.

Last updated: March 12, 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.