**William Beckner** (born September 15, 1941) is an American mathematician, known for his work in harmonic analysis, especially geometric inequalities. He is the Paul V. Montgomery Centennial Memorial Professor in Mathematics at The University of Texas at Austin.

Beckner earned his Bachelor of Science in physics from the University of Missouri in Columbia, Missouri in 1963, where he became a member of the Phi Beta Kappa Society. He later earned his Ph.D. in mathematics at Princeton University in Princeton, New Jersey, where his doctoral adviser was Elias Stein. He also completed some postgraduate work in mathematics under adviser A.P. Calderon at the University of Chicago.

Salem Prize
Sloan Fellow
Fellow of the American Mathematical Society.
Beckner, William (1975). "Inequalities in Fourier Analysis". *Annals of Mathematics*. **102** (1): 159–182. doi:10.2307/1970980.
Beckner, William (1993). "Sharp Sobolev inequalities on the sphere and the Moser–Trudinger inequality". *Annals of Mathematics*. **138**: 213–242. doi:10.2307/2946638.
Beckner, William (1995). "Geometric inequalities in Fourier analysis". *Essays on Fourier Analysis in Honor of Elias M. Stein*. Princeton University Press. pp. 36–68. JSTOR j.ctt7ztk2g.