This question was asked as we were driving to collect my toddler from nursery. My elder child, who had been told that you should never put anything smaller than your elbow in your ear*, was thinking about the size of her ears.
(*Advice from my Grandma who knew full well that you can’t get your elbow in your ear!)
I suggested that we guess how big an eardrum is, then look up the answer when we got home. I thought that an eardrum would be about 1cm2. She guessed that her eardrum would be the same size as the fingernail on her pinkie finger.
As you might expect, the size of an eardrum varies according to the size of the person – a child’s eardrums will be smaller than those of a grown-up – but, according to the Ear Institute of Chicago, the average size for an eardrum is 8 x 10mm.
The eardrum is a membrane (a bit like a flap of skin) inside the ear. It vibrates when sound waves bump into it. Vibrations inside your ear send messages to your brain that allow you to hear sounds. Here’s a description of how hearing works, which includes more detailed information about the eardrum.
The eardrum is very important because it helps you to hear. It can also protect the inner parts of your ear from loud noises. If you damage or ‘pop’ your eardrum, it can be very painful but it will usually get better on its own within a few weeks or months.