Mitchell was born in New Jersey on 23 May 1913. Her mother, a nurse during the 1918 Spanish Flu pandemic, insisted she wash her hands regularly as a child. Her factory worker father stressed the importance of homework and studying.

When Mitchell graduated in 1932, she was among the 8.8% of students who would finish 12th grade that year. In 1937, she married John Douglas Mitchell, the son of Scottish immigrants, at a quiet ceremony in a New Jersey judge’s office. He worked as a decorator and contractor, and, in 1940, Mitchell was employed as a saleswoman at Silver’s 5¢ to $1 store. The couple had no children.

After her husband left to serve in World War II, Mitchell entered the workforce and kept working after his return because “she liked getting paid.” In 1950, she acquired a job as an office clerk at Tepper’s, a department store in South Plainfield, New Jersey. Her husband was a member of the New Jersey Free and Accepted Masons, and she recalled attending dance parties held by the group.

In 1953, Mitchell worked at her final job at the Plainfield Saving and Loan Association, where she worked as a teller and later as assistant treasurer before she and her husband moved to Ventura, California, where they lived with their border collie.

The Mitchells lived in Ventura for many years before returning to New Jersey, settling in Lakewood. She was widowed in 2003. As a centenarian, her hobbies included eating bacon and scrambled eggs, reading novels, watching Jeopardy, and writing letters to her acquaintances. At the age of 110, she lives in a nursing home and is reported to stay active.