At the age of 16 he enrolled at the University of Sydney where he studied organic chemistry. He graduated in 1937 with a bachelor’s degree in science with first class honors and the university medal. By this time, he was fully, completely deaf. After his studies, he went on to get a scholarship to work at Oxford. During his time at Oxford he worked with Robert Robinson he earned two more scholarships. When Rita Harradence (Also from Sydney, Australia)
received a scholarship as well John Cornforth and Rita became partners and soon got married in 1941.
After John finished his work at oxford he went on to help with the chemical effort on penicillin still working with Robinson. He moved on to become a professor at the University Warwick. To communicate to his students, he would read lips and write most of their lessons. A few years past and he decided to be a professor at the University of Sussex instead.
While still a professor at Sussex University, in 1946 he joined the National Institute for Medical Research. John along with Konrad Bloch created a complete carbon-by-carbon degradation of the nineteen-carbon ring structure of cholesterol and to identify, using means radioactive tracers, the arrangement of the acetic acid molecules.
In 1967 he left the service of the medical research council to co-direct the Milstead Laboratory of Chemical Enzymology set up by Shell Research. At his time there John Contributed to the development of the study of the stereochemistry of enzymic reactions by means of asymmetry artificially introduced by isotopic substitution.
Later on, he was promoted to Royal Society researcher at the University of Sussex. John along with two other men solved the problem of the "asymmetric methyl group". His work got tones of recognition the chemical society awarder him the Ernest Guenther award, he was also awarder the Biochemical Society's Ciba medal, along with the Royal society's Davy Medal.
After retirement, he continued to work at the University of Sussex until age 86. John Cornforth died at age 90 in 2013