John Simpson was born in Cheltenham, where his father was employed at GCHQ, and attended Dean Close School.

He was Co-Editor of the Second Edition of the OED, published in 1989, and in 1993 was appointed Chief Editor, a position he held until his retirement in October 2013.

As Chief Editor, he led the first comprehensive revision of the OED and oversaw the introduction of its online version.

[5][6] He was appointed Officer of the Order of the British Empire (OBE) in the 2014 Birthday Honours for services to literature.

[8] His memoir The Word Detective, which tells the story of his time at the Oxford English Dictionary, was published in October 2016 by Little, Brown and in 2017 in paperback by Abacus Books.