When do you need to write numbers in words?
- Cheques/checks: The written amount must match the numeric amount
- Legal documents: Contracts often require amounts written in words
- Formal writing: Style guides recommend writing numbers under 10 in words
- Education: Teaching children to read and write numbers
- Vietnamese documents: Official documents require amounts in Vietnamese words
Rules for writing numbers in English
Basic rules
- Numbers 1–9: always write as words (one, two, three...)
- Numbers 10+: can use numerals in informal writing
- Large round numbers: write as "1 million" not "1,000,000" in running text
- Beginning of sentence: always write as word (never start with a numeral)
Cardinal vs Ordinal
- Cardinal: count (one, two, three) — how many
- Ordinal: order (first, second, third) — what position
| Number |
Cardinal |
Ordinal |
| 1 |
one |
first |
| 2 |
two |
second |
| 3 |
three |
third |
| 4 |
four |
fourth |
| 21 |
twenty-one |
twenty-first |
Currency format
99.50 → "ninety-nine dollars and fifty cents"
1,000 → "one thousand dollars"
Vietnamese number words
| Number |
Vietnamese |
| 1 |
một |
| 10 |
mười |
| 100 |
một trăm |
| 1,000 |
một nghìn |
| 1,000,000 |
một triệu |
| 1,000,000,000 |
một tỷ |
Special Vietnamese rules
Vietnamese has unique rules that differ from direct translation:
- Unit digit 1 after tens becomes mốt (not một): 21 = "hai mươi mốt"
- Unit digit 5 after tens becomes lăm (not năm): 25 = "hai mươi lăm"
- Single digit after hundreds uses linh: 101 = "một trăm linh một"
How to convert numbers to words free
- Go to Numbers to Words
- Type any number
- Select format: Cardinal, Ordinal, or Currency
- Select language: English or Vietnamese
- Copy the result
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