Why Do Cats Purr? Contentment, Comfort and Pain

The happy purr

The purr most owners know comes when a cat is curled on a lap, being stroked, kneading a blanket or settling down to sleep. The body is loose, the eyes may be half-closed or slowly blinking, and the tail is relaxed. In this setting purring is a sign of comfort and of trust in the person or place, and many cats purr more around the people they know best.

Purring begins very early. Kittens purr while nursing, and their mother purrs back, which may help keep the litter close and calm. Many adult cats seem to carry the habit into the situations that feel most like that: warmth, softness, food and a familiar person.

Purring to ask for something

Some cats purr to get what they want, most often food. Owners often notice a slightly different, more insistent purr near mealtime, sometimes mixed with a meow, while the cat winds around their legs or sits by the bowl. VCA notes that cats largely meow at people rather than at each other, and many seem to use purring in a similar targeted way.

If your cat purrs loudly at 5 a.m. next to your pillow, the message is usually breakfast. The best way to keep this from escalating is to avoid rewarding it immediately; feeding on a fixed schedule, or using a timed feeder, takes the urgency out of the morning chorus.

When purring means pain or stress

Cats are very good at hiding illness, an instinct from ancestors that risked becoming prey if they looked weak. VCA warns that a purring cat is not always a happy one: purring can accompany pain, and some cats purr when frightened at the vet, during labor or when badly unwell. Researchers think the purr may help them calm themselves.

Look at the whole picture. A cat purring while hiding under the bed, hunched, not eating, reluctant to jump, or with flattened ears is not content. VCA advises a prompt vet visit if your cat is purring more than usual along with other changes, such as reluctance to use stairs or jump onto furniture, hiding or lower energy.

How cats make the purring sound

The purr is made in the larynx, or voice box. Muscles there twitch rapidly, opening and closing the space between the vocal cords as the cat breathes in and out, which is why a purr can carry on continuously without a break for breath. The exact control mechanism is still being studied.

Because it runs on both the in-breath and the out-breath, a purr can be very loud in some cats and almost silent in others, felt more than heard. Neither is a problem. A cat whose purr suddenly sounds hoarse or different, or who starts to wheeze or breathe noisily, should be checked by a vet.

Reading your cat's purr

To understand a purr, pair it with body language. Relaxed muscles, soft eyes, slow blinks, kneading and a gently curled tail point to contentment. Tense muscles, a tucked tail, dilated pupils, ears turned back, hiding or a change in appetite point toward stress or discomfort.

Notice changes over time. A cat that suddenly purrs in odd places, purrs while lying alone more than usual, or stops purring when it always used to may be telling you something about how it feels. Keeping regular checkups helps catch the quiet illnesses, such as arthritis and dental pain, that cats so often mask.

This page is general information, not veterinary advice, and it cannot replace an examination by the vet who knows your pet.