1000000000 in Japanese
十億

Updated June 2026

1,000,000,000 in Japanese is 十億, written じゅうおく in hiragana and read jū-oku. A billion: ten oku

NUMERAL

1,000,000,000

KANJI

十億

HIRAGANA

じゅうおく

ROMAJI

jū-oku

Real sentence examples

世界の人口は約八十億人です (sekai no jinkou wa yaku hachi-jū-oku-nin desu): the world’s population is around 8 billion.

十億円の予算が組まれました (jū-oku-en no yosan ga kumaremashita): a 1 billion yen budget was prepared.

Pronunciation and morphology notes

One billion (English) is jū-oku in Japanese: ten oku, which is 10 x 100,000,000 = 1,000,000,000. There is no single Japanese word for “billion”. The boundary with the next major unit cho (兆, 10^12) comes at hyaku-oku (100 oku, 10 billion English) and sen-oku (1000 oku, 100 billion English); above that, switch to cho.

Frequently asked questions

How do you write 1,000,000,000 in Japanese?

1,000,000,000 is written 十億 in kanji and じゅうおく in hiragana. In romaji (modified Hepburn) it is jū-oku.

What is 1,000,000,000 in hiragana?

1,000,000,000 in hiragana is じゅうおく. Hiragana spells out the reading jū-oku phonetically; the kanji form is 十億.

Related numbers

100,000,000

一億

ichi-oku

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