Head-to-head comparison across 1benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
Claude 4 Sonnet
50
Mellum2-12B-A2.5B-Instruct
27
Pick Claude 4 Sonnet if you want the stronger benchmark profile. Mellum2-12B-A2.5B-Instruct only becomes the better choice if its workflow or ecosystem matters more than the raw scoreboard.
Coding
+35.5 difference
Claude 4 Sonnet
Mellum2-12B-A2.5B-Instruct
$3 / $15
N/A
40 t/s
N/A
1.33s
N/A
200K
128K
Pick Claude 4 Sonnet if you want the stronger benchmark profile. Mellum2-12B-A2.5B-Instruct only becomes the better choice if its workflow or ecosystem matters more than the raw scoreboard.
Claude 4 Sonnet is clearly ahead on the provisional aggregate, 50 to 27. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude 4 Sonnet's sharpest advantage is in coding, where it averages 72.7 against 37.2.
Claude 4 Sonnet gives you the larger context window at 200K, compared with 128K for Mellum2-12B-A2.5B-Instruct.
Claude 4 Sonnet is ahead on BenchLM's provisional leaderboard, 50 to 27.
Claude 4 Sonnet has the edge for coding in this comparison, averaging 72.7 versus 37.2. Mellum2-12B-A2.5B-Instruct stays close enough that the answer can still flip depending on your workload.
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