一日(ついたち)

Pronunciation

The same kanji have two readings:

• ついたち: first day of the month
• いちにち: one day (duration)

Counting patterns

Days of the month, 1st–10th (irregular readings):

• 一日(ついたち) (1st)
• 二日(ふつか) (2nd)
• 三日(みっか) (3rd)
• 四日(よっか) (4th)
• 五日(いつか) (5th)
• 六日(むいか) (6th)
• 七日(なのか) (7th)
• 八日(ようか) (8th)
• 九日(ここのか) (9th)
• 十日(とおか) (10th)

After the 10th, most days use the regular Sino-Japanese reading: 十一日(じゅういちにち), 十二日(じゅうににち), etc. A few days after the 10th keep irregular readings: 十四日(じゅうよっか), 二十日(はつか), 二十四日(にじゅうよっか).