Cats produce purring by rapidly twitching muscles in their voice box while breathing.

The purring sound is created when a cat’s brain sends signals to muscles in its larynx, or voice box. These muscles twitch quickly, opening and closing a small space in the throat called the glottis. As the cat breathes in and out, air passes through this vibrating opening, producing the familiar purring noise. This happens about 25 to 150 times per second, creating a steady, rhythmic sound that we recognize instantly as a cat’s purr.