Subdivision surface modifier issue I'm following Blender guru's Anvil tutorial. After using Boolean I cleaned up the extra vertices. Edge flow looks fine on my mesh. 

However, when I apply a Subdivision Surface modifier my mesh becomes really messy as if something is wrong with the edge flow. 

Can you guys help spot the problem?

Mesh topology:



Subdivision issue:
Even though your edge flow looks good from the side, the base of your mesh is apparently made by a single big N-gon.

Compare the subdivision of a quad base vs a n-gon base:



You should remove your base face and replace it with carefully created quadrilaterals.