Badly and slowly — the blade is narrower than a clipper’s and the guards are shaped for a face, so it works in an emergency and is not the tool.
A clipper blade is wide precisely because a scalp is a large area. A beard trimmer blade is narrow because a jawline is not.
The result is many more passes, a longer job and more chance of unevenness at the joins between them.
There is a second problem at the long end: most beard trimmers stop between 12 and 21 mm (0.83 in), which is shorter than a lot of people wear their hair on top.
Where the two genuinely meet is an all-in-one kit, which shares a motor between a clipper-width head and a trimmer-width one. Several on this site do exactly that, and their pages state which attachments are included.
Last reviewed August 22, 2026