100000000 in Japanese
一億

Updated June 2026

100,000,000 in Japanese is 一億, written いちおく in hiragana and read ichi-oku. 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.

Frequently asked questions

How do you write 100,000,000 in Japanese?

100,000,000 is written 一億 in kanji and いちおく in hiragana. In romaji (modified Hepburn) it is ichi-oku.

What is 100,000,000 in hiragana?

100,000,000 in hiragana is いちおく. Hiragana spells out the reading ichi-oku phonetically; the kanji form is 一億.

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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