This pinyin converter turns pinyin with numbers into pinyin with tone marks.

Enter pinyin followed by numbers 1-4 represent the Chinese tones.  For neutral tone words, either type 5 or no number at all.  Use the letter “v” for the “ü” character.  Press convert to add the tones.

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Now supports apostrophes! (e.g. Xi1an1 -> Xī’ān)
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