French rules
| Rule | Example |
|---|---|
| “et” only in 21, 31, 41, 51, 61 and 71 | vingt et un, soixante et onze, but quatre-vingt-un |
| vingt and cent take an s when multiplied and last | quatre-vingts, deux cents, but deux cent un |
| …and before million or milliard (nouns) | deux cents millions |
| …but not before mille (invariable) | deux cent mille, quatre-vingt mille |
| mille never takes an s, nor “un” before it | mille, deux mille |
| million, milliard are nouns | un million, deux millions |
The 1990 spelling reform (rectifications orthographiques, recommended by the Académie française) links every numeral with hyphens: vingt-et-un, deux-cents, mille-deux-cents. The nouns million and milliard stay separated by spaces.
Large numbers use the long scale in French (milliard = 10⁹, billion = 10¹²) and the short scale in English (billion = 10⁹).
English
US style by default (one hundred one); UK style inserts “and” (one hundred and one). Decimals are read digit by digit: 3.14 → three point one four.