Sunita Williams was born in Euclid, Ohio, to Indian American neuroanatomist Deepak Pandya and Slovene American Ursuline Bonnie Pandya (née Zalokar), who have three children and reside in Falmouth, Massachusetts.
Sunita is the youngest of three siblings; her brother Jay Thomas is
four years older and her sister Dina Anna is three years older.
Williams’ paternal ancestry is from Jhulasan, Mehsana district in Gujarat, India, while her maternal great-grandmother Mary Bohinc (originally Marija Bohinjec), born 5 September 1890 in Leše, Slovenia immigrated to America as an eleven-year-old girl with her mother, an 1891 Slovene emigrant Ursula Bohinc née Strajhar.
Williams graduated from Needham High School in Needham, Massachusetts, in 1983. She received a Bachelor of Science degree in physical science from the United States Naval Academy in 1987, and a Master of Science degree in Engineering Management from Florida Institute of Technology in 1995.