GPT-5.4 Pro vs LFM2.5-1.2B-Instruct

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

GPT-5.4 Pro is clearly ahead on the aggregate, 91 to 30. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.4 Pro's sharpest advantage is in coding, where it averages 87.4 against 7.2. The single biggest benchmark swing on the page is SWE-bench Pro, 89 to 6.

GPT-5.4 Pro is also the more expensive model on tokens at $30.00 input / $180.00 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for LFM2.5-1.2B-Instruct. That is roughly Infinityx on output cost alone. GPT-5.4 Pro is the reasoning model in the pair, while LFM2.5-1.2B-Instruct 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. GPT-5.4 Pro gives you the larger context window at 1.05M, compared with 32K for LFM2.5-1.2B-Instruct.

Quick Verdict

Pick GPT-5.4 Pro if you want the stronger benchmark profile. LFM2.5-1.2B-Instruct only becomes the better choice if you want the cheaper token bill or you would rather avoid the extra latency and token burn of a reasoning model.

Agentic

GPT-5.4 Pro

GPT-5.4 Pro

87.4

LFM2.5-1.2B-Instruct

25.7

90
Terminal-Bench 2.0
22
88
BrowseComp
31
84
OSWorld-Verified
26

Coding

GPT-5.4 Pro

GPT-5.4 Pro

87.4

LFM2.5-1.2B-Instruct

7.2

95
HumanEval
14
86
SWE-bench Verified
9
86
LiveCodeBench
8
89
SWE-bench Pro
6

Multimodal & Grounded

GPT-5.4 Pro

GPT-5.4 Pro

94.9

LFM2.5-1.2B-Instruct

32.4

94
MMMU-Pro
27
96
OfficeQA Pro
39

Reasoning

GPT-5.4 Pro

GPT-5.4 Pro

96.1

LFM2.5-1.2B-Instruct

32.1

97
SimpleQA
24
95
MuSR
22
98
BBH
59
95
LongBench v2
34
97
MRCRv2
37

Knowledge

GPT-5.4 Pro

GPT-5.4 Pro

83.8

LFM2.5-1.2B-Instruct

26

99
MMLU
26
99
GPQA
25
97
SuperGPQA
23
94
OpenBookQA
21
94
MMLU-Pro
50
50
HLE
1
92
FrontierScience
30

Instruction Following

GPT-5.4 Pro

GPT-5.4 Pro

97

LFM2.5-1.2B-Instruct

80

97
IFEval
80

Multilingual

GPT-5.4 Pro

GPT-5.4 Pro

95.7

LFM2.5-1.2B-Instruct

60.7

97
MGSM
62
95
MMLU-ProX
60

Mathematics

GPT-5.4 Pro

GPT-5.4 Pro

98.2

LFM2.5-1.2B-Instruct

37

99
AIME 2023
24
99
AIME 2024
26
99
AIME 2025
25
96
HMMT Feb 2023
20
98
HMMT Feb 2024
22
97
HMMT Feb 2025
21
97
BRUMO 2025
23
99
MATH-500
54

Frequently Asked Questions

Which is better, GPT-5.4 Pro or LFM2.5-1.2B-Instruct?

GPT-5.4 Pro is ahead overall, 91 to 30. The biggest single separator in this matchup is SWE-bench Pro, where the scores are 89 and 6.

Which is better for knowledge tasks, GPT-5.4 Pro or LFM2.5-1.2B-Instruct?

GPT-5.4 Pro has the edge for knowledge tasks in this comparison, averaging 83.8 versus 26. Inside this category, GPQA is the benchmark that creates the most daylight between them.

Which is better for coding, GPT-5.4 Pro or LFM2.5-1.2B-Instruct?

GPT-5.4 Pro has the edge for coding in this comparison, averaging 87.4 versus 7.2. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.

Which is better for math, GPT-5.4 Pro or LFM2.5-1.2B-Instruct?

GPT-5.4 Pro has the edge for math in this comparison, averaging 98.2 versus 37. Inside this category, HMMT Feb 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, GPT-5.4 Pro or LFM2.5-1.2B-Instruct?

GPT-5.4 Pro has the edge for reasoning in this comparison, averaging 96.1 versus 32.1. Inside this category, SimpleQA is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, GPT-5.4 Pro or LFM2.5-1.2B-Instruct?

GPT-5.4 Pro has the edge for agentic tasks in this comparison, averaging 87.4 versus 25.7. 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, GPT-5.4 Pro or LFM2.5-1.2B-Instruct?

GPT-5.4 Pro has the edge for multimodal and grounded tasks in this comparison, averaging 94.9 versus 32.4. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, GPT-5.4 Pro or LFM2.5-1.2B-Instruct?

GPT-5.4 Pro has the edge for instruction following in this comparison, averaging 97 versus 80. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, GPT-5.4 Pro or LFM2.5-1.2B-Instruct?

GPT-5.4 Pro has the edge for multilingual tasks in this comparison, averaging 95.7 versus 60.7. Inside this category, MGSM is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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