He was educated at Market Harborough Grammar School and afterwards at King William's College, Isle of Man. He studied mathematics at Trinity College, Cambridge, in 1881. He studied physics in the Cavendish Laboratory during part of 1885, and at the end of that year was elected to the Professorship of Mathematics and Physics in the University of Adelaide, South Australia. Subsequently he became Cavendish Professor of Physics at Leeds (1909-1915), then Quain Professor of Physics at University College London (1915-1925), and Fullerian Professor of Chemistry in the Royal Institution.

His research interests covered many topics and he was skilled at picking up a subject, almost casually, making an important contribution, then dropping it again. However, the work of Bragg and his son Lawrence in 1913-1914 founded a new branch of science of extreme importance and significance, the analysis of crystal structure by means of X-rays.

The use of X-rays as an instrument for the discovery of the way in which crystals are built was entirely due to the Braggs. This was recognized by the award of the Nobel Prize jointly to father and son in 1915.

After a brilliant life, Sir William Bragg died on March 10, 1942.