Extended Arabic-Indic Digit Zero

It is zero in Persian, Urdu, and Sindhi numbers.

Zero holds an empty place in positional arithmetic, so the digits around it keep their value. Indian place-value arithmetic was known in Arabic-speaking lands by the seventh century. Around 776, an Indian astronomical work was ordered translated, and al-Khwarizmi's arithmetic belongs to the ninth century. Together, these milestones trace the method's route through Arabic scholarly culture.

Persianate bookkeepers also used siāq, a separate accounting shorthand with no zero; its earliest surviving records date from the early tenth century. By the middle of the tenth century, an arithmetic manual praised Indian numerals as quick and easy to use on paper. The wider numeral system took different written shapes as it spread from India through Arabic scholarly culture and onward into Europe.

Why is ۰ different from 0?

The value is the same; the character and convention differ.

0 is the Latin zero; ٠ is the Arabic-Indic zero associated with Arabic-language text; ۰ is the Eastern Arabic-Indic zero used with Persian, Urdu, and Sindhi. In Persianate notation, abjad letter-values—using letters as numbers—were an older system. Place-value digits gradually took over everyday arithmetic, while abjad remained useful for chronograms, dates encoded in words, and book front matter.

Some typefaces draw ۰ and ٠ similarly. In right-to-left text, the two sets also have distinct bidirectional behavior, so substituting one can change how nearby punctuation displays.