Ƙididdigar Ƙididdiga ta Amurka don Musanya Bayanai (ASCII) ƙa'idar ce ta ɓoye haruffa wacce ke ba da lambobi na musamman ga haruffa, alamomi, da sauran haruffa waɗanda aka saba amfani da su a cikin harshen Ingilishi. An kirkiro ASCII a cikin 1960s ta Ƙungiyar Ƙwararrun Ƙwararrun Amirka (ASA), wadda daga bisani ta zama Cibiyar Ƙididdiga ta Amirka (ANSI). Ana amfani da lambobin ASCII sosai a cikin kwamfuta da tsarin sadarwa don wakiltar rubutu da sauran bayanai, kuma ƙasashe da yawa na duniya sun karbe su a matsayin ma'auni.