Katharine Burr Blodgett was born in Schenectady, New York, to George Reddington Blodgett, a patent attorney at General Electric, and Katharine Buchanan Burr. Her father's work at GE would later influence her career path significantly.

George Reddington Blodgett was murdered in his home, which led Katharine, her mother, and brother to move to France for several years. This experience exposed her to a broader world and fostered independence.

Katharine received a portion of her early education in France, exposing her to different cultures and ways of learning, fostering a broader intellectual curiosity.

The Blodgett family returned to the United States. Katharine continued her education at a private school in New York City.

Katharine attended Bryn Mawr College, where she studied physics and mathematics. She was deeply inspired by her professors and excelled in her studies, laying the groundwork for her scientific career.

During a visit to the General Electric research laboratory, Irving Langmuir (a friend of her family and future Nobel laureate) gave her a tour. He showed her his work and inspired her to pursue scientific research. This pivotal visit influenced her decision to pursue graduate studies.

Blodgett earned her Master's degree in physics from the University of Chicago in 1920. Her thesis was on the adsorption of gases on charcoal, demonstrating her early interest in surface chemistry.