[[File:999 Perspective.svg|300px|class=skin-invert-image|thumbnail|Stylistic impression of the number, representing how its decimals go on infinitely]]

In [[mathematics]], '''0.999...''' (also written as '''0.{{overline|9}}''', '''0.{{overset|.|9}}''', or '''0.(9)''') denotes the smallest number greater than every [[number]] in the sequence {{nowrap|(0.9, 0.99, 0.999, ...)}}. It can be proved that this number is{{spaces}}1; that is,

Despite common misconceptions, 0.999... is not "almost exactly 1" or "very, very nearly but not quite 1"; rather, 0.999... and "1" are {{em|exactly}} the same number.