How Well Cats Hear: A Quick Guide

How well cats hear is sometimes overlooked, but their ability to hear low and high frequencies, distinguish sounds, and pinpoint the location of a sound is unbelievable. I’m always honest that cat vision compared to ours isn’t the best (though it serves them for hunting!). But cats’ hearing is not only better than ours, but better than most mammals. In this quick guide, I’ll explain how their ears are designed to aid in hunting and why their abilities far surpass most others.

Kitten Hearing

Kittens are born blind and deaf and are 100% dependent on their mother. Although the auditory system technically “works,” the actual canal is blocked by ridges of skin, preventing sound from traveling through. Kittens make some responses to sound around day 5 even though the canal isn’t open because the ears start to unfold. They start to squint (with their eyes closed), move their ears, sniff, and lift and move their heads. The canal widens over 10-15 days as the pinna (visible part of the ear) continue to unfold. It’s apparent by head movements that kittens locate the source of a sound at day 16 and follow a sound by day 21.

By 3-4 weeks, kittens can tell the difference between inner species calls. While they approach their mother’s calls, they pull back and flatten ears if they hear growls or male threats. At 4 weeks, kittens have well-developed hearing.

Cat Ear Structure & How Cats Hear

Cat ears have 3 parts: outer, middle, and inner ear. Here’s a breakdown of each part and the role it plays in hearing.

Outer Ear

Parts of the outer ear include:

• Pinnae – Visible part of the ears that are upright and cone-shaped. They collect and naturally amplify sound 2-3x for frequencies 2,000-6,000 Hertz. Pinnae are independently mobile up to 180 degrees with 32 muscles (humans have 6). They can be pointed at or away from a sound (like when you call your cat’s name and they shift toward you).
• Ear canal – Shaped like an L on its side, with almost a 90-degree angle, it carries sounds to the eardrum.

Pinnae cause changes to a sound as it passes to the ear canal. The cat’s brain uses the changes to determine how far away the sound is and if it’s coming from above or below. Pinnae are also directional amplifiers, sensitive to frequencies of cat vocalizations, which is very helpful for mating. This is the only part of their ears that isn’t designed for hunting.

The ear canal in cats is much deeper and more tapered than in humans, and does a better job at getting sound to the eardrum.

Middle Ear

According to Merck Manual, there are two parts to the middle ear:

• Eardrum – A membrane that vibrates in response to sound.
• Tympanic cavity – Small, air-filled chamber that holds 3 tiny auditory ossicles (bones) that vibrate in response to sound.
• Eustachian tube – Connects to the back of the throat, allowing air to enter and maintaining pressure in the middle ear.
• Oval window – Connects the middle ear to the inner ear.

Sounds travels through the ear canal in waves that hit the eardrum and make it vibrate. When the eardrum vibrates, the bones in the tympanic cavity move and push the fluid-filled membrane at one end of the cochlea in the inner ear.

Inner Ear

As PetPlace explains, inner ear contains the:

• Cochlea – Holds nerves that transmit electrical impulses responsible for hearing. A cat’s cochlea has 40,000 nerve fibers transmitting sound from the ear to the brain. That’s 25% more than humans.
• Vestibule and 3 semicircular fluid-filled canals – When the cat’s head moves, the fluid moves and tells the brain which direction and how much the head is moving, helping with balance.

Waves in the fluid flow over hair-like cells that stick inward from the floor of the cochlea and move. Depending on which cells are moved, a cat will hear different sounds. These cells send signals to the brain and the brain processes them into sound.

Broad Frequency Range

Frequency is also called pitch, and it’s the number of times per second a sound wave repeats itself. High-frequency sounds produce more repetitions, whereas low-frequency sounds produce fewer. Units of frequency are measured in Hertz (Hz). Cats can detect sound variations as slight as one-tenth of a pitch. They can also tell what made the sound and how big it is.

At low frequencies, cats and humans are similar, with cats at 55 Hz and humans at 20 Hz. It’s at higher frequencies that cats really excel. Adult human hearing maxes out around 20,000 Hz, but that decreases to 12,000 – 15,000 Hz as we age. Our feline friends can hear up to 64,000 Hz, 1.6 octaves higher and 3x better than us and 1 octave higher than dogs (45,000 Hz). Sounds at a higher frequency than what we hear is referred to ultrasound and is necessary for the type of prey cats hunt. They can hear ultrasonic pulses bats use, as well as the sounds of mice of other rodents and identify rodents by squeaks. Although mice and rats can hear high frequencies, they cannot hear lower frequencies as well as cats. The rodents that most closely line up with the hearing abilities of cats include gerbils, guinea pigs, and ferrets.

What Makes Cats Unique

The fact that cats can hear low frequencies given the size of their heads is impressive. It’s also impressive because typically when a mammal can hear low frequency sounds, they can’t also hear ultrasound. Cats have a unique inner ear structure, with an exceptionally large resonating chamber behind the eardrum. This chamber has a unique feature not found in other mammals – it divides into two interconnecting compartments and increases the range of frequencies the eardrum will vibrate for.

Cat hearing is so good, they can hear sounds 4-5x farther away than us.

Location, Location

The very first action in the hunting process is when a cat hears scratching, rustling, or high-frequency noises – then, they start seeking their prey.

From only 3 feet away, a cat can distinguish sounds 3 inches apart in .06 seconds. That means if there were two rodents, they would know which one was making a sound.

Their brains analyze the differences between sounds coming from the right and left ear to locate the source. Lower frequency sounds arrive at one ear slightly out of sync with the other. Higher frequencies are muffled by the time they reach the ear farthest from the source, which also helps determine location. When hearing ultrasounds, the muffling effect gets larger, further helping the cat determine where the sound is coming from.

Deafness in Dominant White Cats

Like us, hearing loss can be congenital or acquired, but there is one group of cats that is more common to be deaf: dominant white cats.

Deafness is associated with the dominant white gene (DW), which is not related to albinism. These cats are white all over because the gene prevents pigmented cells from migrating to the skin during embryonic development. In this way, it masks the actual color the cat would normally be. These kittens are often born with a few colored hairs on their heads that eventually turn white.

Because of the imbalance of melanocytes (pigment-related cells) in the inner ear, the cochlea degenerates starting a few days after birth. Deafness is most common in dominant white cats with blue eyes. Here’s the breakdown:

• Non-blue eyes: 17-22%
• 1 blue eye: 40%
• 2 blue eyes: 65-85%

(Note: Not all white cats are dominant white cats. A cat that has some white on it has the white spotting gene (Ws), and in rare cases, the white spotting gene can be represented all over the body, making the cat completely white.)

Henry’s Pocket

A cutaneous marginal pouch, aka Henry’s pocket, is the little pocket of skin at the outside base of the cat’s ear. Other animals have Henry’s pocket (including some dogs, as well as bats and weasels) and it’s purpose is unknown. One theory is it muffles low-frequency sounds and amplifies high-frequency sounds from potential prey. Henry’s pocket might also help the cat better move and clean its ears. Better movement also improve communication between cats since they rely mostly on body language and pheromones (non-verbal methods of communication).

I Hear You

There is no question that cats have an incredible sense of hearing. Keep in mind when it’s quiet and a cat looks up like they heard something, they very well may hear something you aren’t capable of hearing!

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