Karmarkar was born in Kolhapur, India, on 19 March 1909, the son of Hari Dattatraya Karmarkar, a general practitioner, and Savitri Hari Karmarkar, a housewife. He was educated at the King George High School, Mudhol, and Deccan College of Arts, Poona, from which he went to study medicine at the Seth Gordhandas Sunderdas Medical College and King Edward Memorial Hospital, Bombay. After junior posts, he went to England to study for the FRCS, attending the lectures of Samson Wright at the Middlesex Hospital and the clinical course at St Bartholomew's. He returned to India for further experience at the Sevashram Hospital and was appointed surgeon and honorary professor to the G T Hospital, Bombay, and later to his old teaching hospital, the King Edward Memorial Hospital. He was visiting surgeon to the Karnatak Health Institute from 1949 to 1959. He was a member of the Association of Surgeons, the Indian Medical Association and a founder member, and later honorary Fellow, of the International College of Surgeons. In 1934, he married Pramila Ramchandra and had four daughters and one son, Suhas R Karmarkar FRCS Edinburgh, who trained in the Cleveland Clinic and returned to be Professor of Surgery in Lok Tilak Medical College. His daughter Anjali Kulkarni is a gynaecologist in Bombay. He died in February 2001.