1/5

1/5 may refer to:


 * January 5, the date
 * 1 May, the date
 * quintile, a 5-quantile in statistics
 * one fifth, the reciprocal of the number 5, = 0.2
 * one and five, 1 shilling and 5 pence in pre-decimal British Coinage
 * 1st Battalion 5th Marines
 * one to five betting odds