Head-to-head comparison across 2benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
Mellum2-12B-A2.5B-Instruct
27
o1
57
Pick o1 if you want the stronger benchmark profile. Mellum2-12B-A2.5B-Instruct only becomes the better choice if you would rather avoid the extra latency and token burn of a reasoning model.
Knowledge
+34.8 difference
Inst. Following
+16.4 difference
Mellum2-12B-A2.5B-Instruct
o1
N/A
$15 / $60
N/A
98 t/s
N/A
32.29s
128K
200K
Pick o1 if you want the stronger benchmark profile. Mellum2-12B-A2.5B-Instruct only becomes the better choice if you would rather avoid the extra latency and token burn of a reasoning model.
o1 is clearly ahead on the provisional aggregate, 57 to 27. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
o1's sharpest advantage is in knowledge, where it averages 75.7 against 40.9. The single biggest benchmark swing on the page is GPQA, 40.9% to 75.7%.
o1 is the reasoning model in the pair, while Mellum2-12B-A2.5B-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. o1 gives you the larger context window at 200K, compared with 128K for Mellum2-12B-A2.5B-Instruct.
o1 is ahead on BenchLM's provisional leaderboard, 57 to 27. The biggest single separator in this matchup is GPQA, where the scores are 40.9% and 75.7%.
o1 has the edge for knowledge tasks in this comparison, averaging 75.7 versus 40.9. Inside this category, GPQA is the benchmark that creates the most daylight between them.
o1 has the edge for instruction following in this comparison, averaging 92.2 versus 75.8. Inside this category, IFEval is the benchmark that creates the most daylight between them.
For engineers, researchers, and the plain curious — a weekly brief on new models, ranking shifts, and pricing changes.
Free. No spam. Unsubscribe anytime.