When did Ludwig van Beethoven begin to lose his hearing?

Ludwig van Beethoven was not born deaf, but he experienced a gradual loss of hearing throughout his life. The first symptoms of his impairment, which included buzzing and ringing in his ears, manifested before 1800.12

By 1802, Beethoven realized that his condition was both permanent and progressive, a struggle he documented in the "Heiligenstadt Testament". Despite this, he continued to compose throughout his life, creating many of his most famous works while partially or totally deaf. His hearing loss did not become total until approximately 1819, after which he relied on conversation books to communicate with others.21