Think about how you feel when you hear your cat purr. If you’re like most cat parents, the sound immediately fills you with happiness and love for your pet. Cats are special, but they can also be somewhat of a mystery.
Luckily, through years of research by veterinarians, animal behaviorists, and dedicated cat lovers, we have a much better understanding of this trademark feline sound.
So, why do cats purr? What does it mean? Is it always a good thing? Let’s take a closer look.
How Do Cats Purr?
Cats start to purr at just a few days old, which shows how innate this sound and behavior is for our feline companions. But it’s not just domestic cats that purr; scientists have documented other cats in the Felidae family, like the bobcat, cheetah, and puma, making the same noise.
However, it’s a common misconception that other big cats — jaguars, lions, and leopards, most notably — can also purr. While they make a purr-like noise, it isn’t produced in the same way or for similar reasons.
But, for those lucky few that are able to purr, how exactly do they do it?
The honest answer is that no one knows for sure, although research keeps moving us closer to a conclusive answer. Specifically, one crucial part of the feline body is involved — the larynx (also known as the “voice box”).
Like humans, the larynx is vital in allowing your cat to vocalize as it contains the vocal cords. The larynx also protects your cat from aspirating by closing and creating a seal between the mouth and the lungs.
The intrinsic (or internal) laryngeal muscles help control the larynx and are the most likely part of the body responsible for allowing your cat to purr. They help open and close the space between the vocal cords, called the glottis, creating that unique purring sound.
What makes purring distinct from other noises that cats make is that purring occurs during both inhalation and exhalation, unlike meowing or hissing. Your cat breathing in or out has little to no effect on the volume or quality of their purr.
Like those other vocalizations, though, purring is at least partly voluntary, which is part of why it can be such a powerful communication tool.
Why Do Cats Purr?
Now that we have a better idea of how cats purr, let’s talk about why they might make that noise. Although much of what we know about purring is second-hand — because they can’t speak up and tell us how they feel using words — we can make educated guesses (just like we do with other feline behaviors like the “zoomies”).
We’ve compiled four of the most likely reasons a cat might make a purring noise and how you can tell which one you may be dealing with. Think of a cat purring as similar to a human laughing — while the noise may be the same, the reason behind it can vary depending on the situation.
You have to look at the bigger picture to interpret it accurately; the noise is just a single piece of a much larger puzzle.
When They’re Happy
The number one theory is that it’s a vocal indicator of how happy they’re feeling at that moment. From the time they’re small, cats purr in response to positive stimuli — dinner time, cuddle time, etc.
These positive experiences may become part of their unconscious, so any time they feel safe and happy, purring is their go-to way to express it. Purring may also release the same endorphins in your cat that we get from petting them, keeping that happy feeling even longer.
If you want to be sure that your cat is purring because they’re happy, start by looking at their body language and what’s happening around them. Are they lying in a sunbeam in their favorite spot? Are they lounging on your lap while you pet them?
If your cat seems relaxed and has their eyes closed (or partially closed) and their tail mostly still, you can safely assume it’s a happy purr.
Cats don’t always purr out of happiness, though. In some situations, a cat may make a purring sound for the same reasons a young child sucks their thumb — it’s a way to self-soothe if they’re feeling stressed out or out of control.
Think about how it would feel if you couldn’t tell the people around you how you were feeling, especially if you were going through a period of stress or anxiety. If you notice that your cat seems to be purring at inappropriate times or your cat’s purr is higher in pitch than usual, pay attention to what’s happening around them.
Interestingly, the frequency has been measured at between 25 and 150 Hertz. This frequency has also shown potential for healing (especially bone healing) and pain reduction, not just in cats but in humans too.
Your cat doesn’t know that they may be doing something beneficial for their health when they purr to self-soothe, but the benefits are there nonetheless. Some cats even participate in a behavior some call “purr therapy,” where they lay next to another cat that may be in distress and purr.
While this is not as common, cats may also purr as a way to de-escalate any potential conflict. Like other vocalizations, purring is a way to communicate a message. If your cat has housemates they struggle to be getting along with, and you hear them purring when the other cat is around, they may be trying to make peace.
In these situations, purring may be a way to tell the other cat that they are not a threat. It’s often seen in less aggressive cats, similar to how a more submissive animal would bow to a more dominant one (although feline dominance is far more subtle).
A cat that purrs to de-escalate conflict is likely feeling scared and insecure, making it more critical for you to step in and find ways to help make the situation safer for everyone. The last thing you want is for a conflict to turn physical because that’s a challenging situation to come back from.
Ultimately, purring is a form of communication for your cat. It’s just one tool that your cat can use to express how they feel. Alongside meowing, hissing, chirping, chattering, and growling, purring allows them to bridge the gap between human and feline modes of communication so they can get their point across.
One thing that cats may purr to communicate is hunger. From the time they’re born, cats use purring to tell their mother that they’re hungry. While there is still plenty of debate about how cats view their human roommates, they definitely understand that you’re the person that makes food happen.
They may not think you’re their mother, per se, but they know that communicating with you fills their food bowl. That’s why hungry purrs and related vocalizations can often mimic the sound a human baby would make — it works nearly every time.
What Should You Do When Your Cat Is Purring?
The first thing you should do when your cat is purring is to take a moment to decipher why. In most cases, it’s easy to identify the source of the purring. However, if your cat doesn’t seem to be relaxed or enjoying themselves, you can look a little deeper to see if anything is bothering them.
If your cat seems to be purring as a form of self-soothing as opposed to out of sheer happiness, look into ways you can reduce their stress level. Consider consulting an animal behaviorist or scheduling an appointment with your veterinarian, who can rule out physical stressors and discuss options (like potential CBD supplementation). If your cat is having trouble with a housemate, consider separating them to minimize both cats’ stress levels.
Otherwise, if your cat is purring and there are no signs of distress, enjoy it! Spend some cuddle time with your cat — studies have shown that having pets can lower your blood pressure and may even reduce your risk of developing cardiovascular disease and related mortality.
Cat purring can be just as healing for you as it is for them, plus it offers you an opportunity to deepen your bond with an animal that loves you unconditionally.
Why Do Cats Purr: The Bottom Line
Why do cats purr? While we can only make an educated guess, purring likely means various things depending on the situation. The best action you can take is to make sure you pay attention to your cat’s vocalizations — each of them is a way for your pet to communicate their feelings, wants, and needs.
Being a good cat owner means reading between the lines and doing everything possible to make your pets’ lives happy, healthy, and long. Learning to interpret what they’re trying to get across can help improve both of your lives and make your bond even closer.