What does roach feces look like?
Generally speaking, cockroach droppings are dark brown or black pellets. They’re either roundish chunks or oval-shaped, and much of what you find will simply appear as smears and stains on the surfaces that cockroaches have been crawling over.
Of course, before a full-blown infestation, roach droppings will be so minimal and scattered that you may not even see them. While on the other hand, during a large infestation they’ll be almost impossible to miss, along with other nasty cockroach stuff like egg cases, discarded shells, and cockroach body parts.