Khorana was born in Raipur (at that time India, now Pakistan). In 1945, he began studies at the University of Liverpool. After earning a Ph. D., he spend a postdoc year in Zürich (1948-49). He then returned to England and worked at Cambridge until 1952. He married Esther Elizabeth Sibler the same year. After that, he worked at universities in Vancouver and Wisconsin.
Khorana was awarded the 1968 Nobel Prize in Medicine (together with Robert W. Holley and Marshall W. Nirenberg) for describing the genetic code and how it operates in protein synthesis.