How deep microwaves penetrate food?

Microwaves penetrate food to a depth of about 1 to 2 inches, depending on the food's composition, density, and moisture content. In denser foods, microwaves may not penetrate as deeply, leading to uneven cooking if not properly stirred or rotated. The heat generated by the microwaves causes water molecules in the food to vibrate, producing heat that cooks the food from the inside out.