The modern numeral 0 is normally written as a circle or (rounded) rectangle. In old-style fonts with text figures, 0 is usually the same height as a lowercase x.
ð ə WORD_BOUNDARY m ɑ d ə ɹ n WORD_BOUNDARY n uː m ə ɹ ɹ ə l WORD_BOUNDARY z iə ɹ oʊ WORD_BOUNDARY ɪ z WORD_BOUNDARY n ɔ ɹ m ə l i WORD_BOUNDARY ɹ ɪ t ə n WORD_BOUNDARY æ z WORD_BOUNDARY ʌ WORD_BOUNDARY s ɜː k ə l WORD_BOUNDARY ɔ ɹ WORD_BOUNDARY ɹ aʊ n d ɪ d WORD_BOUNDARY ɹ ɛ k t æ ŋ ɡ ə l WORD_BOUNDARY ɪ n WORD_BOUNDARY oʊ l d s t aɪ l WORD_BOUNDARY f ɔ n t s WORD_BOUNDARY w ɪ ð WORD_BOUNDARY t ɛ k s t WORD_BOUNDARY f ɪ ɡ j ə ɹ z WORD_BOUNDARY z iə ɹ oʊ WORD_BOUNDARY ɪ z WORD_BOUNDARY j uː ʒ uː ə l i WORD_BOUNDARY ð ə WORD_BOUNDARY s eɪ m WORD_BOUNDARY h aɪ t WORD_BOUNDARY æ z WORD_BOUNDARY ʌ WORD_BOUNDARY l oʊ ə ɹ k eɪ s WORD_BOUNDARY ɛ k s WORD_BOUNDARY