I would make it so big it makes colonies.

Big but not big enough to cause issues

Akko hat be like

I'd live in it!

like 800cm diameter

Door frames are never big enough

triple my head size uwu

big

biiiiiig

Regular size.

nah I am not much of a witch

it would not just be a witch hat, but a witch home. i would live inside

Very big

slightly to big to walk through doors without issues

A size that would shatter reality itself