PIPE CHART ( OUTSIDE WALL DIAMETER ) ACTUAL OUTER DIAMETER ACTUAL OUTER DIAMETER ACTUAL OUTER DIAMETER FRACTIONAL INCHSIZE ACTUAL OUTSIDE DIAMETER 1/8″ = .125″ 1/4″ = .250″ 3/8″ = .375″ 1/2″ = .500″ 3/4″ = .750″ 1″ = 1.000″ 1 1/4″ = 1.25″ 1 1/2″ = 1.500″ 2″ = 2.000″ 2 1/2″ = 2.500″ 3″ = 3.000″ 3 1/2″ = 3.500″ 4″ = 4.000″ 4 1/2″ = 4.500″ 5″ = 5.000″ 6″ = 6.000″ THIN WALL INCH SIZE (E.M.T.) ACTUAL OUTSIDE DIAMETER 1/2″ = .706″ 3/4″ = .922″ 1″ = 1.163″ 1 1/4″ = 1.503″ 1 1/2″ = 1.738″ 2″ = 2.195″ 2 1/2″ = 2.875″ 3″ = 3.500″ 3 1/2″ = 4.000″ 4″ = 4.500″ HEAVY WALL INCH SIZE & PIPE(RIGID) ACTUAL OUTSIDE DIAMETER 1/8″ = .405″ 1/4″ = .540″ 3/8″ = .675″ 1/2″ = .840″ 3/4″ = 1.050″ 1″ = 1.315″ 1 1/4″ = 1.660″ 1 1/2″ = 1.900″ 2″ = 2.375″ 2 1/2″ = 2.875″ 3″ = 3.500″ 3 1/2″ = 4.000″ 4″ = 4.500″ 4 1/2″ = 5.000″ 5″ = 5.563″ 6″ = 6.625″