Press the buttons to play the tones that go from 8Hz all the way up to 22,000Hz to check your hearing, its fairly common for people who are over 25 years of age to not be able to hear above 15kHz and also experience some level of hearing loss or hearing damage such as tinnitus. This online test will help you find out where your high frequency hearing cuts off. If you cant hear sounds below 15 kHz, you should get you hearing checked.