Updated 29 May 2026
The sound of a feline purring contentedly is music to a cat lover’s ears, but have you ever found yourself wondering, “why do cats and kittens purr?” The reason is more complex than you might think.

Why do cats and kittens purr?
People often interpret purring as a sign of happiness and contentment. And it can be, but that’s not all it means.
As a means of communication, your cat may purr to:
- Potentially tell their mother they’re hungry
- Capture our attention and communicate with other animals
- Tell us they’re relaxed and happy
- Potentially self sooth when they’re sad, stressed, or sad
This simple rumbling sound has many potential emotional meanings, not just happiness, which makes it difficult to assign the sound to any one feeling. To figure out exactly what your cat is trying to tell you, you’ll need to look at the bigger picture they paint with their body language.
Why do cats and kittens purr when they feel stressed?
Cats also purr when they’re distressed, afraid or in pain, and even when giving birth, so it could be that it’s a self-soothing behaviour. Some believe that this purring may release endorphins to help pacify them when they’re under duress.
How can I tell if my cat is purring from happiness?
In addition to purring, their body language will be happy. Signs that your cat is happy include:
- Tail held straight up, possibly quivering
- Eyes half closed with narrow pupils
- Whickers to the side
- Kneading on a soft surface
How can I tell if my cat is purring from stress?
If your cat is trying to self-soothe through purring, they may show other signs of stress and anxiety:
- Crouched low to the ground
- Ears flat on their head
- Tail bushy and/or tucked between their legs
How do cats purr?
It’s not known precisely how cats purr. One popular theory is that they use the muscles in their voice box to rapidly expand and contract the vocal folds up to 30 times per second. The resulting vibrations as they breathe in and out are what we hear as purring.
Interestingly, no cat is able to both purr and roar – which is no doubt good news for Australia’s three million domestic cat owners! They’re not the only purring animals either – rabbits and guinea pigs have also been known to purr.
At what age kittens start purring?
Most kittens begin purring and vocalising around three weeks of age, though some make take a bit longer to find their voice.
Why do I love the sound of my cat’s purr so much?
A cat’s purr is one of the best sounds in the world. But why does hearing this rumble from our cats make us so happy? It’s thought to come down to sound frequencies.
Sound frequency and vibrations can have particular effects on the body depending on the range it is in. Think about certain genres of music and the way each one can affect your mood – it’s not just the sound working its magic, it’s the vibrations too.
It has been found that domestic cats purr at a frequency of 25 to 150 vibrations per second. The range occupied by cat’s purrs has been found to be therapeutic for bone growth, pain relief and even wound healing. These findings haven’t just been observed in cats – they’ve been observed in humans and other animals around them as well. Cats may just be the superior species after all!
About the Author
At Petbarn, we believe that life is better with pets. From high quality products to trusted advice, we're here to provide you with everything you need to care for your furred, feathered, and finned friends.