Born in Melbourne, Kerr learnt to swim at Albert Park Lake, and won medals at both the Victorian and Australasian championships in 1905, at the age of 17.
Early the following year, she toured South Australia and Western Australia, winning every race she entered.
From there, Kerr went to England, giving swimming exhibitions in Bradford, Liverpool, London, and Manchester, being billed as "Australia's Champion Lady Swimmer and Diver".
She returned to Australia in October 1911, living the rest of her life in Sydney, New South Wales.
Although often compared to Annette Kellerman, another Australian swimmer, Kerr's repeated challenges to Kellerman to race went unanswered.