My wife is sewing adult custom masks in four different sizes, with two layers of cotton and a pocket in the middle so you can insert a blue shop towel paper filter. She also adds a rubber-coated wire to the top, so it can be molded around your nose. They don't leak at all, if you pick the right size. She's sending them to friends and extended family.

I'm sure a correctly sealed N95 mask is better, but most of us can't get them.