The hearing range of the domestic cat is one of the broadest among all the mammals. A study published in 1985 concluded that “the hearing range of the cat for sounds of 70 dB extends from 48 Hz to 85 kHz, giving it one of the broadest hearing ranges among mammals.”
They further concluded that this extended hearing range evolved over eons to be able to receive high-frequency sounds from their most common prey item, the mouse and other small ground dwelling mammals. And this development occurred without sacrifice to their low-frequency hearing.
The range of hearing that I quote above appears not to be set in concrete because you will find different answers to the cat’s hearing range. For example, Dr. Desmond Morris in his book Cat World states that cats “can hear sounds up to an astonishing 100,000 cps. This corresponds well to the high pitch of mouse calls, which can be emitted up to the same level. So, no mouse is safe from the alert ears of the predatory cat”.
The “100,000 cps” is a reference to cycles per second which, in other words, means 100 kHz. Desmond Morris, is, therefore stating that the hearing of the domestic cat extends to a hundred kilohertz which is well beyond the 85 kHz stated by the study scientists.
Wikipedia have a chart in which it is stated that the cat has a hearing range of 55 Hz-77 kHz. This is a substantially narrower range than found by the study.
By comparison, it is worthwhile stating that the dog has a hearing range of 64 Hz-44 kHz according to Wikipedia. Another educational website states that the dog has a hearing range of 45 Hz-64 kHz. Once again, a different conclusion.
And, Linda P Case in her book The Cat, Its Behaviour, Nutrition and Health, states that “cats can detect sounds as high as 60,000 to 80,000 cps”. She also states that the “cat’s lower audible frequencies are estimated to be between 20 cps and 55 cps”. Female mice communicate with their offspring using squeaks ranging from 17,000 and 80,000 cps.
By comparison, Desmond Morris states that the higher frequency limit for humans in the prime of their life is about 20,000 cps or 20 kHz. This is reduced to around 12 kHz in humans of retirement age. And so, we can see that the upper frequency limit for humans is around a quarter of that of domestic cats.
This is one reason why cats are alerted to sounds that we can’t hear. When their ears pricked forward and they look intently at something that we are unaware of they have no doubt heard something that we can’t hear.
Kittens, at birth, have blocked ear canals by ridges of skin. They gradually open up as the canal widens during the first two weeks of life. They don’t develop the ability to locate sounds in the environment until they are two weeks of age. By four weeks it is well developed.
P.S. Years ago, I discussed the mysterious Henry’s pocket; an interesting structure on the cat’s ear flap which improves sound detection (see link below). You might like to investigate and add to the discussion. A visitor disagreed with me and commented. I made a page out of his comment which you can read by clicking on this link.