She was born in Washingtone DC in 1924 and was raised primarily by her mother Julia and her aunt Louise after her parents separeted. Both her mother and aunt worked for the US Bureau of Engraving and Printing. Despite the family's small size in DC, they had roots in Orange County, Virginia, and often spent summers there. Evelyn attended Dunbar High School, one of the few options for Black students due to segregation, and graduated as one of five valedictorians in 1941.

Evelyn Boyd, driven by her desire for higher education, applied to Smith and Mount Holyoke colleges, opting for Smith due to her admiration for a Black professional woman who attended there. Despite lacking scholarships, her family and Phi Delta Kappa provided financial assistance, enabling her to attend Smith. Evelyn's college experience was marked by academic excellence, initially intending to study French but ultimately gravitating towards mathematics, physics, and astronomy. Working part-time at Smith and summers at the National Bureau of Standards, she supported herself through her studies. Evelyn graduated summa cum laude from Smith in 1945, majoring in mathematics and physics, and was elected to Phi Beta Kappa.

Evelyn Boyd earned numerous awards for graduate studies, including fellowships at Yale University and the University of Michigan. At Yale, she obtained her Master's and PhD in Mathematics, with her dissertation focusing on "On Laguerre Series in the Complex Domain." Following her doctorate, she conducted a post-doctorate at New York University before becoming an associate professor at Fisk University in Nashville, where she mentored future mathematicians like Vivienne Malone Mayes and Etta Zuber Falconer.

In 1952, Dr. Boyd joined the National Bureau of Standards in Washington, DC, working on missile fuse development. She later transitioned to computer programming, initially with IBM in Washington, then as a consultant in New York City. Her expertise led her to NASA's Vanguard Computing Center in DC, where she developed software to track satellite and spacecraft orbits. Dr. Boyd's multidisciplinary background in mathematics, physics, and astronomy from Smith College positioned her as a pioneering figure in early computer science.

After leaving IBM in 1960, Dr. Boyd relocated to Los Angeles, where she contributed to research on orbit computation at the United States Space Technology Laboratories. She then joined North American Aviation (NAA) in 1962 as a research specialist in celestial mechanics, trajectory, and orbit computation for the Apollo project. Returning briefly to IBM in 1963, she later declined a relocation offer and decided to stay in Southern California.

The Soviet launch of Sputnik in 1957 and Yuri Gagarin's orbit in 1961 spurred the US to establish Project Mercury, leading to Alan Shepard's and John Glenn's space missions. President Kennedy's goal to land a man on the moon by the end of the 1960s initiated NASA's Apollo program. Dr. Boyd's team, with mathematician Katherine G. Johnson, validated orbit trajectories crucial for missions like Glenn's. Their efforts contributed to the success of the Apollo program, culminating in Neil Armstrong and Buzz Aldrin's moon landing in 1969.