Hefner was born in Chicago, Illinois, the elder of two sons born to Grace Caroline Swanson (1895-1997) and Glenn Lucius Hefner (1896-1976), both teachers. He went to Sayre Elementary School and Steinmetz High School, then served as a writer for a military newspaper in the U.S. Army from 1944-1946. He later graduated from the University of Illinois at Urbana-Champaign with a B.A. in psychology with a double minor in creative writing and art in 1949, earning his degree in two and a half years. After graduation, he took a semester of graduate courses in sociology and women and gender studies at Northwestern University but dropped out soon after.
Working as a copywriter for Esquire, he left in January 1952 after being denied a $5 raise. In 1953, he lent his furniture for $600 and raised $8,000 from 45 investors – including $1,000 from his mother (“Not because she believed in the venture,” he told E! in 2006. “But because she believed in her son”) – to launch Playboy, which was initially going to be called Stag Party. The undated first issue, published in December 1953, featured Marilyn Monroe from her 1949 nude calendar shoot. Hefner, who never met Monroe, owns the crypt next to hers.