Spelling of French numbers

Numbers

Numbers are not really easy to write in French. You never know where to put a dash or a s. Please find the complete rules.

Single words

A few numbers can be written by a single word. They are:

* numbers until 16: zéro, un, deux, trois, quatre, cinq, six, sept, huit, neuf, dix, onze, douze, treize, quatorze, quinze and seize.
* then ten until 60: vingt, trente, quarante, cinquante and soixante.
* and finally 100 and 1000: cent and mille.

Compound words

When it is not possible to use a single word, numbers are compound by several single words. You need to know when to put a dash.

You have to put a dash in all compound numbers less than 100 who do not end with 1 except 81 and 91:

* dix-sept, quarante-huit...
* quatre cent cinquante-trois...

For numbers terminated in 1, you have to add word et:

* soixante et un
* soixante et onze
* cinquante et un

81 and 91 are written with a dash:

* quatre-vingt-un
* quatre-vingt-onze

Locale usage

In Belgium and Switzerland, 70 and 90 are septante and nonante. Then, compound numbers follow the same rules:

* septante et un
* nonante-trois

In Switzerland, huitante is used for 80. It appears that octante is also used but personally I never heard it.

All these characteristics come from former French. To know why septante and nonante are not used anymore is a still mystery. But one explanation would come from the king Louis XIV.
His reign was very long. Feeling to age, it did not wish to change ten. Thus he invented a stratagem to remain young. He was sixty nine years old and the following year, sixty ten. That makes much younger than seventy! Then, for his eighty years old, easy, he became younger than ever because he had four times twenty years. After all, he was called the Roi soleil (Sun King)!

Others said it comes from the old 20 basis regularly used in the Middle Age in Europe.

Plural

20 and 100 agree when they are multiplied by a number without being followed by another number.

* quatre-vingts
* quatre-vingt-trois
* quatre cents
* quatre cent vingt et un

Mille is always invariable

* trois mille * dix mille deux

un is invariable in number but not in gender:

* cinquante et une pages

Millier, million and millard are noun and not adjective. They agree:

* quatre cents millions
* deux cent mille
* deux cents milliers

Mille can be written mil but only in a date.

* l'an mil quatre cent trois

Some of these cardinal numeral adjectives can have an ordinal value to express year, day, parts of a work, street number, sovereign name... They remain invariable:

* l'année mille neuf cent (la 1900e)
* le quinze juin (le quinzième jour de juin)
* la page quatre-vingt (80e)
* le tome deux
* habiter au cinquante-huit
* Louis quatorze, Charles dix...

Plural starts at 2. We wrote:

* 1,9 point
* 2 points
* 1,9 million
* 2 millions

Ordinal numeral adjective

It is composed by adding suffix ième to the corresponding number (except premier and second):

* trois ; troisième
* quatre ; quatrième
* cent ; centième
* mille ; millième...

For abbreviations, final letters are used. Abbreviation of "ième" is e without accent, because it is the last letter:

* 1^er = premier
* 1^re = première
* 2^d = second
* 2^de = seconde
* 2^e = deuxième
* 2^es = deuxièmes

Contrary to the cardinal adjective, it agrees in gender and number with the reference noun:

* les premiers froids... * les dixièmes jeux Olympiques...

It takes a dash when it is a composed number inferior to one hundred:

* la vingt-cinquième heure...

Recommended spelling

In 1990, the French Academy introduced new speling rules. It is now easier to write small numbers. All numbers are composed with a dash: trois-cent-vingt-quatre.

Note: This is only recommendations, this is not compulsory.