Why does my cat sleep on my chest or lap so often?

A cat choosing your body as a sleeping spot is generally read as a sign of a secure, trusting bond, since sleep is the most vulnerable state an animal enters and cats are selective about where they do it. Your chest specifically also offers warmth, a steady heartbeat and the rise and fall of breathing, all of which read as calming rather than random comfort. Cats also gravitate toward warm surfaces in general, so a lap in a cool room is competing with radiators and sunny windowsills, not just with you. If it stops suddenly and she avoids contact instead, that shift is more worth noting than the habit itself.