Million/Billion/Trillion Converter — 万/億/兆 (Free)

Instantly convert big numbers between Japanese units (万, 億, 兆) and English units (million, billion, trillion), with a quick-reference table and real examples.

Last updated: 2026-08-26

Complete Japanese–English Unit Reference

Every named unit from 10⁰ (one) to 10¹⁰⁰ (googol), side by side.

Exponent	Japanese	English
10⁰	一（いち）	one
10¹	十（じゅう）	ten
10²	百（ひゃく）	hundred
10³	千（せん）	thousand
10⁴	万（まん）	—
10⁶	—	million
10⁸	億（おく）	—
10⁹	—	billion
10¹²	兆（ちょう）	trillion
10¹⁵	—	quadrillion
10¹⁶	京（けい）	—
10¹⁸	—	quintillion
10²⁰	垓（がい）	—
10²¹	—	sextillion
10²⁴	秭（じょ）	septillion
10²⁷	—	octillion
10²⁸	穰（じょう）	—
10³⁰	—	nonillion
10³²	溝（こう）	—
10³³	—	decillion
10³⁶	澗（かん）	undecillion
10³⁹	—	duodecillion
10⁴⁰	正（せい）	—
10⁴²	—	tredecillion
10⁴⁴	載（さい）	—
10⁴⁵	—	quattuordecillion
10⁴⁸	極（ごく）	quindecillion
10⁵¹	—	sexdecillion
10⁵²	恒河沙（こうがしゃ）	—
10⁵⁴	—	septendecillion
10⁵⁶	阿僧祇（あそうぎ）	—
10⁵⁷	—	octodecillion
10⁶⁰	那由他（なゆた）	novemdecillion
10⁶³	—	vigintillion
10⁶⁴	不可思議（ふかしぎ）	—
10⁶⁸	無量大数（むりょうたいすう）	—
10¹⁰⁰	—	googol

🟢 Green rows mark where Japanese and English share a name for the same exponent (e.g. 10¹²: 兆 = trillion). 🟡 The amber row 10¹⁰⁰ is googol — the number that inspired the name "Google".

Million, Billion, Trillion vs 万・億・兆: What This Converter Does

Japanese large-number units (万, 億, 兆) and English large-number units (million, billion, trillion) do not line up one to one, and that mismatch trips up even experienced translators and business writers. Japanese counts in blocks of four digits — each new unit (万, 億, 兆, 京) marks a jump of 10,000×. English counts in blocks of three digits — each new unit (thousand, million, billion, trillion) marks a jump of 1,000×. Because the two systems are built on different-sized blocks, a round number in one language rarely stays round in the other. This is exactly why "1億円" so often gets mistranslated as "1 million yen" instead of the correct "100 million yen": the translator assumes the units simply swap out, when in fact the whole scale has shifted.

This tool removes the guesswork. Type a number in either Japanese notation or plain digits (including scientific notation like 1e9), and it instantly shows you the equivalent in both Japanese units (万, 億, 兆) and English units (million, billion, trillion), correctly grouped for each system. Beyond one-off conversions, the page also includes real-world reference points — Earth's diameter, the world's population, the age of the universe, Japan's GDP — and a complete Japanese–English unit table running from 10⁰ all the way to 10¹⁰⁰ (the googol), so you can build a lasting intuition for how the two numbering systems relate, not just look up a single answer and forget it.

How to Convert Between 万・億・兆 and Million/Billion/Trillion

Enter the number you want to convert Type it as plain digits or scientific notation — for example 350000000 or 3.5e8 both work, and you can also paste a comma-separated figure like 8,000,000,000.
Read off the Japanese notation The result appears broken into 万 / 億 / 兆 groupings, matching how the number would actually be written and spoken in Japanese.
Read off the English notation At the same time, the equivalent English figure appears using thousand / million / billion / trillion groupings, so you can see exactly which English word corresponds to your number.
Cross-check with the quick-reference table If you need a nearby order of magnitude, or want to confirm the English name for a specific Japanese unit, click any row in the tables further down the page — the value fills straight into the input.
Scan the real-world examples for a sense of scale Compare your number against the built-in examples, such as world population (about 8 billion / 80億) or Japan's GDP (about 591 trillion yen / 591兆円), to judge whether your figure is large, small, or roughly in between.

Tips for getting more out of it

When you see "億" (10^8), the English is hundred million. "1億円 = 1 million yen" is a common mistake — the correct translation is 100 million yen.
"10億" = 1 billion. When you hear "a billion dollars" in English news, think of it as 10億ドル in Japanese.
"1兆" = 1 trillion (= 10^12). This unit lines up in both languages. Japan's national budget is about 110兆円; the US GDP is roughly 25 trillion dollars.
"100万" = 1 million (= 10^6). "Million" only appears at the 1,000,000 mark.

When You Need to Convert Million, Billion, and Trillion to 万・億・兆

Reading foreign news and earnings reports

When an overseas company's earnings release says "revenue of $1.2 billion," you can immediately grasp the scale in familiar terms before you even think about the yen conversion.

Translating or drafting English-language releases

When rendering a Japanese figure like "〇億円" or "〇兆円" into English, this tool keeps you from mixing up million, billion, and trillion — a mistake that can understate or overstate a number by orders of magnitude.

Double-checking investor materials and pitch decks

IR reports and pitch decks often need revenue, valuation, or market-size figures restated in English units; use the converter as a quick sanity check before the numbers go out the door.

Studying place value in school math

Students learning how Japanese place value (万・億・兆) compares with English place value (thousand・million・billion) can use the side-by-side tables as a hands-on learning aid.

Making sense of scientific and astronomical figures

Numbers like the age of the universe (about 13.8 billion years) or the Earth–Sun distance (about 149.6 billion meters) are much easier to reason about once you see both notations side by side.

Glossary: 万進法, 千進法, and Large-Number Terms

Myriad system (万進法): The traditional East Asian counting system, used in Japanese, where a new unit name is introduced every four digits: 万 (10,000), 億 (100 million), 兆 (1 trillion), 京 (10 quadrillion), and beyond. "Myriad" itself is an old English word for 10,000, which is where the name comes from.
Thousand system: The standard counting system in English, where a new unit name is introduced every three digits: thousand (10³), million (10⁶), billion (10⁹), trillion (10¹²). Because it groups by threes rather than fours, its unit boundaries fall at different points than the Japanese system.
Million: The English unit for 10⁶, or one thousand thousand. Since the Japanese unit 万 (man) is 10⁴, one million is equal to 100万 — the two are related, but never a simple 1-for-1 swap.
Billion: The English unit for 10⁹, equal to 10億 in Japanese. Older British English once used "billion" to mean 10¹², but that usage has been obsolete for decades — today both American and British English agree that a billion is 10⁹.
Trillion: The English unit for 10¹², which happens to match the Japanese unit 兆 (chō) exactly. It is one of the few points where the myriad system and the thousand system land on the same number, which is why it is worth memorizing as a fixed reference point.
億 (oku): The Japanese unit for 10⁸, equal to 100 million in English. This is the unit most often mistranslated, since writers instinctively reach for "million" instead of the correct "hundred million."
兆 (chō): The Japanese unit for 10¹², equal to one trillion in English. National budgets and GDP figures are commonly expressed in 兆 (chō) in Japanese sources, so recognizing this unit is essential for reading Japanese economic news.
Scientific notation (e-notation): A compact way of writing very large or very small numbers as "mantissa e exponent," such as 1e9. Here, 1e9 means 1 × 10⁹, or one billion — this format is accepted directly as input.

FAQ

It's 100 million yen. "1 million yen" refers to 100万円 (1,000,000 yen), so don't confuse the two.

"1兆" equals 1 trillion (10^12). This is one of the few units that lines up directly between Japanese and English.

The tool supports numbers up to 999兆 (999 trillion, roughly 10^15). Values above that will return an error.

Side Note — Why the 4-digit vs 3-digit gap exists

The Japanese large-number system, inherited from ancient China, uses a myriad-based (万進法) system — units change every four digits: 万, 億, 兆, 京… Standard English uses a thousand-based system — thousand, million, billion… As a result, 10,000 (1万) has no single English word and must be written as "ten thousand."

The confusion is especially common in business and media. "How much is 10億円?" — since 10億 = 10^9 = 1 billion, the answer is "1 billion yen." A frequent error is translating 1億円 as "1 million yen," when the correct expression is "100 million yen." Use this converter to get it right every time.

Browse all trivia