Katharine Way was born in Sewickley, Pennsylvania, the second child of William Addisson Way, a lawyer, and his wife Louise Jones. She had an older brother and a younger sister. Originally named Catherine, she later changed the spelling to Katharine. Friends and colleagues generally knew her as Kay. Her mother died when she was twelve years old, and her father married an ear and throat specialist, who provided Kay with a role model of a career woman. Way was educated at Miss Hartridge's boarding school in Plainfield, New Jersey, and Rosemary Hall in Greenwich, Connecticut. In 1920 she entered Vassar College, but was forced to drop out after two years after becoming ill with suspected tuberculosis. After convalescing in Saranac Lake, New York, she attended Barnard College for two semesters in 1924 and 1925. From 1929 to 1934 she studied at Columbia University, where Edward Kasner stoked an interest in mathematics, and co-authored Way's first published academic paper. She graduated with her BS in 1932. She next went to the University of North Carolina, where John Wheeler stimulated an interest in nuclear physics, and she became his first PhD student. Because jobs were hard to come by during the Great Depression, she stayed on as a graduate student after completing the requirements of her PhD. In 1938, she became a Huff Research Fellow at Bryn Mawr College, which allowed her to receive her PhD for her thesis on nuclear physics, "Photoelectric Cross Section of the Deuteron". She subsequently took up a teaching position at the University of Tennessee in 1939, becoming an assistant professor in 1941. At a conference in New York in 1938, Way presented a paper, "Nuclear Quadrupole and Magnetic Moments", in which she examined deformation of a spinning atomic nucleus under three models, including Niels Bohr's liquid drop model. She followed this up with a closer examination of the liquid drop model in a paper entitled "The Liquid-Drop Model and Nuclear Moments", in which she showed that the resulting cigar-shaped nucleus could be unstable. Wheeler later recalled that:
Way moved to Washington, D.C., in 1949, where she went to work for the National Bureau of Standards. Four years later, she persuaded the National Academy of Sciences' National Research Council to establish the Nuclear Data Project, an organization with special responsibility for gathering and disseminating nuclear data, under her leadership. The NDP moved to the Oak Ridge National Laboratory in 1964, but Way remained its head until 1968. Beginning in 1964, the NDP published a journal, Nuclear Data Sheets, to disseminate the information that the NDP had gathered. This was joined the following year by a second journal, Atomic Data and Nuclear Data Tables. She also persuaded the editors of Nuclear Physics to add keywords to the subject headings of articles to facilitate cross-referencing. Way left the NDP in 1968 and became an adjunct professor at Duke University in Durham, North Carolina, although she continued as editor of Nuclear Data Sheets until 1973, and Atomic Data and Nuclear Data Tables until 1982. In later life she became interested in the health problems of seniors, and lobbied for improved health care for them. Way, who never married, died at Chapel Hill, North Carolina, on December 9, 1995.