100000000 in Japanese
一億

Updated May 2026

A hundred million: 1 oku, the next major unit

NUMERAL

100,000,000

KANJI

一億

HIRAGANA

いちおく

ROMAJI

ichi-oku

Real sentence examples

日本の人口は約一億二千万人です (nihon no jinkou wa yaku ichi-oku ni-sen-man-nin desu): Japan's population is around 120 million.

一億円の宝くじが当たったらどうしますか (ichi-oku-en no takarakuji ga atattara dou shimasu ka): what would you do if you won the 100 million yen lottery?

Pronunciation and morphology notes

A hundred million in Japanese is ichi-oku (one oku), the next major unit after man. One oku = 10,000 x 10,000 = 100,000,000 (100 million in English). The Japanese government publishes budgets in oku and cho natively; the budget for the 2024 fiscal year was approximately 112 cho yen. For English-speakers, sliding from 3-digit to 4-digit comma groupings is the key mental shift to read Japanese big numbers fluently.

Related numbers

10,000

一万

ichi-man

10,000,000

千万

sen-man

1,000,000,000

十億

jū-oku

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