Deborah Hertz was born in Saint Paul, Minnesota, in 1949 and graduated from Highland Park Senior High School in 1967. She attended New York University for two years and studied at the Hebrew University in Jerusalem for her junior year abroad in 1969–70. She then returned to the United States and graduated with a major in humanities, summa cum laude, from the University of Minnesota in 1971. She remained at the University of Minnesota and received her PhD in German history in 1979.
After a year of teaching at Pittsburg State University in Kansas, she moved to the State University of New York at Binghamton in 1979 and remained there until 1996. In that year she accepted a position at Sarah Lawrence College in Bronxville, New York. In 2003, Hertz was offered the Herman Wouk Chair in Modern Jewish Studies at the University of California San Diego, and began teaching at UC San Diego in January 2004. In 2008, she founded the Holocaust Living Workshop, a collaboration between the UC San Diego Jewish Studies Program and the Library to preserve the memory of the victims and survivors of the Holocaust.
Hertz has held visiting appointments at the Hebrew University, Tel Aviv University, the University of Haifa, and held two visiting professorships at Harvard University.
Her husband, Martin Bunzl, is a professor of philosophy emeritus at Rutgers University. Deborah Hertz and Martin Bunzl have two grown children.