20 in Japanese
二十
Updated May 2026
Where 20 is also hatachi (age 20)
NUMERAL
20
KANJI
二十
HIRAGANA
にじゅう
ROMAJI
ni-jū
Build-by-place breakdown
Counter-attached forms
How 20 attaches to common counters. Each links to the per-counter deep-dive.
Cultural context
Hatachi (はたち, 二十歳) is the traditional native (Yamato) reading for “20 years old”, surviving from before Sino-Japanese readings displaced the native count above 10. Seijin-no-hi (Coming-of-Age Day, the second Monday of January) celebrates Japanese who turned 20 in the past year. Until 1 April 2022, 20 was the legal age of majority in Japan; this was lowered to 18, but hatachi remains culturally significant.
Real sentence examples
二十歳になりました (hatachi ni narimashita): I've turned 20 years old.
二十人のクラスです (ni-jū-nin no kurasu desu): it's a class of 20 people.
Pronunciation and morphology notes
Twenty in regular counting is ni-ju (2 x 10). But the age 20 uses the totally irregular native form hatachi (二十歳), not ni-jus-sai. The same 二十 kanji can be read either way depending on context: ni-ju when counting, hatachi for age 20. See /counters/age/ for the full age table.
Related numbers
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