How big is a biopsy?

Small, 4mm.: This is usually small, like 4mm for a punch biopsy. Others might be bigger, like breast tissue can be 3-4 cm in greatest dimension.

It depends: Lung, stomach, cervix, colon biopsies usually 1-2 mm in all three dimensions. Liver, kidney biopsy, a cylinder 1-2 mm across by however long. Other organs, however much it takes. Good luck if you have a procedure coming up.