Mavalvala was always interested in math and science as a child, and believed that she was intrinsically good at it, in contrast to the humanities.[10] Mavalvala was raised in the Zoroastrian faith.[3] A lesbian, Mavalvala and her partner have two children and reside in Cambridge, Massachusetts in the United States. Mavalvala has extended family in Karachi and visited the city in 2010.[4][11][12][13][14]