- Cats may purr because they are happy or they want something, like food, from you.
- Mother cats and kittens communicate through purring, so the sound may be a carryover from kittenhood.
- The low vibrations created by purring may actually help your cat ease pain and heal muscles.
- Visit Insider's Health Reference library for more advice.
If you're a cat owner, you're likely familiar with the soothing, rhythmic murmur of your cat's purr as they nap in the afternoon sun or nestle into your lap for a cuddle.
Cats purr with a consistent pattern and frequency between 25 and 150 Hertz, loud enough for humans to hear and feel the purr's vibrations.
Most people associate purring with feelings of pleasure and contentment, but cats actually purr for a number of reasons, including to relieve pain or communicate with other cats.
Here are six reasons why cats purr.
1. Your cat is happy
Purring is often a cat's way of saying they like being touched and want more, says Megan Conrad, BVMS, a veterinarian who works with Hello Ralphie, a telehealth vet provider.
Your cat might also purr while eating or drinking to express feelings of happiness and fulfillment, says Christine Sellers, DVM, a veterinarian at the Cat and Bird Clinic.
2. As a way for mother cats and kittens to communicate
Kittens start to purr when they are only a few days old as a way to communicate and bond with their mothers, Sellers says.
"The mother communicates to her kittens from the day of birth and the kittens communicate back to the mother by purring after they are a few days old," she says.
Because kittens are born deaf and blind, the vibrations from a mother cat's purr can help guide the kittens to nurse.
3. Your cat is stressed
While purring is most commonly associated with an expression of cat happiness, your cat may also purr while stressed or anxious, like when visiting the vet. If your cat is nervous, purring can be a way for them to self-soothe and calm down.
There are a few ways you can tell if your cat is purring because of anxiety, says Sellers:
- An anxious purr may have a slightly higher pitch than a contentment purr.
- The purr is paired with panting or showing teeth
In some cases, like when stressed, purring appears to be intentional while in cases like expressing contentment, purring is more of an automatic reaction, Sellers says.
4. To heal themselves and relieve pain
Some cats purr while in labor or when injured. In these instances, researchers say purring helps ease pain and regulate breathing.
Plus the low-frequency vibration produced by purring can actually stimulate healing, Conrad says, particularly of bones and tendons.
In fact, low-frequency vibrations, similar to the vibrations created by cats when purring, have been used in humans to stimulate bone growth and promote muscle strength.
5. To greet other cats
Your cat might also purr upon seeing another familiar cat as a way to greet them.
Exactly what they are communicating isn't clear yet to scientists, Conrad says, but it could be a way to let the other cat know they are friendly and approachable and to convey the message that they are not a threat.
6. Your cat wants something from you
Purring can also be a way for a cat to express certain needs to its human caregivers, like feeling hungry and wanting food. Purring as a means to receive something from a caregiver tends to be higher pitched and more urgent sounding compared to other types of purring, Sellers says.
According to researchers, humans are more likely to react to this type of urgent, solicitation purr. A 2009 study conducted playbacks of purrs from 10 cats recorded in both solicitation contexts with cries accompanying the purrs and in non-solicitation contexts. The 50 human participants regarded the solicitation purrs as more urgent and less pleasant.
Insider's takeaway
Cats purr for a number of reasons, including to express contentment, to communicate with other cats or animal companions, and to self-soothe during times of stress or injury.
Some cats will produce a more high-pitched, urgent purr when they want something from their human owners, like food.
Whatever the reason, you can usually tell based on context. Look out for other kitty cues to help you understand your cat's needs and preferences, and you'll probably both be happier for it.