Kim Falconer was born in California, and was raised on Wilder Ranch, then a family-owned property and now part of Wilder Ranch State Park: the family name Wilder recurs in her writing name for young-adult fiction, A.K. Wilder.
Falconer moved to Australia in 1981, and holds a Master of Arts degree in writing from Swinburne University of Technology, Melbourne (awarded 2014). Her work falls into the genre of speculative fiction: originally writing for an adult readership, she published her first young-adult novel in 2020.