Danielle Kettlewell was born and raised in Vancouver, Canada to Australian parents. She took up synchronised swimming at age eight after her mother made her take up classes. She retired from swimming competitively at age 18 but continued to be involved recreationally.
In October 2013 she suffered a bad concussion which forced her to drop out of university, but then only one month later and one day after her 21st birthday she discovered she could relocate to Australia with the once in a lifetime opportunity to try out of for the National Team.
She was part of the World Championships team in July 2015 which qualified Australia for the Rio Games. She made her Olympic debut in 2016 where she was vice-captain of the Australian team which placed eighth overall with 75.4333 in the free routine and 74.0667 in the technical.