Mayer was born in 1975 in a small Wisconsin town called Wausau. Her father was an engineer and her mother was an art teacher. Mayer developed an early talent for math and science. Mayer applied to 10 schools and got accepted to all of them, including Harvard, Yale, and Stanford. She ended up going to Stanford, where she first took premed courses, in hopes of becoming a doctor. But her life perspective changed when she took an introductory computer-science class called CS105.
By the time she graduated, Mayer already had 12 job offers lined up. The last offer came from Google, a small startup at the time. Mayer was planning to take a job at management-consulting firm McKinsey at the time. Plus, when she did her own analysis, Google only had a 2% chance of surviving. But she was fascinated by the people and thought she'd learn more there. She took the Google offer — and worked there for the next 13 years.
