French counting behaves itself as far as 69. Then, at 70, it stops naming numbers and starts calculating them.
| Number | French | Literally |
|---|---|---|
| 70 | soixante-dix | sixty-ten |
| 80 | quatre-vingts | four-twenties |
| 90 | quatre-vingt-dix | four-twenties-ten |
| 99 | quatre-vingt-dix-neuf | four-twenties-ten-nine |
It is genuinely arithmetic: 4 × 20 + 10 + 9. Once you see that, the whole range becomes predictable rather than bizarre.
The seventies: keep counting past sixty
There is no French word for seventy. The sixties simply continue to 79 by taking the teens:
| Number | French | Structure |
|---|---|---|
| 70 | soixante-dix | 60 + 10 |
| 71 | soixante et onze | 60 + 11 |
| 72 | soixante-douze | 60 + 12 |
| 75 | soixante-quinze | 60 + 15 |
| 77 | soixante-dix-sept | 60 + 17 |
| 79 | soixante-dix-neuf | 60 + 19 |
Note 71. It takes et — soixante et onze — matching 21, 31, 41, 51 and 61, all of which insert et before un. Seventy-one is the odd member because the joining word appears before onze, not un. From 72 onward the et vanishes.
The eighties: four twenties
| Number | French | Structure |
|---|---|---|
| 80 | quatre-vingts | 4 × 20 |
| 81 | quatre-vingt-un | 4 × 20 + 1 |
| 85 | quatre-vingt-cinq | 4 × 20 + 5 |
| 89 | quatre-vingt-neuf | 4 × 20 + 9 |
Two details to get right. First, 81 is quatre-vingt-un with no et — the pattern from 21 and 31 does not extend here. Second, the s on vingts only survives when nothing follows.
The s rule: quatre-vingts (80) keeps its s because the multiple of twenty is complete. quatre-vingt-un (81) drops it because a number follows. Cent works identically — deux cents for 200, but deux cent un for 201.
The nineties: four twenties plus the teens
| Number | French | Structure |
|---|---|---|
| 90 | quatre-vingt-dix | 4 × 20 + 10 |
| 91 | quatre-vingt-onze | 4 × 20 + 11 |
| 95 | quatre-vingt-quinze | 4 × 20 + 15 |
| 98 | quatre-vingt-dix-huit | 4 × 20 + 18 |
| 99 | quatre-vingt-dix-neuf | 4 × 20 + 19 |
Ninety-one is quatre-vingt-onze, with no et — unlike 71. The two ranges look parallel but differ on exactly this point, which is where most learners slip.
Belgium and Switzerland fixed it
French outside France frequently uses the decimal forms that Old French also had:
| Number | France | Belgium | Switzerland |
|---|---|---|---|
| 70 | soixante-dix | septante | septante |
| 80 | quatre-vingts | quatre-vingts | huitante |
| 90 | quatre-vingt-dix | nonante | nonante |
These are not dialect curiosities to be avoided; they are standard in those countries, used in schools and on the news. Septante-cinq for 75 is entirely ordinary in Brussels. Speakers in France will understand you, though they will place you immediately.
Where the system came from
The usual account points at Celtic substrate influence: Breton and other Celtic languages count in twenties, and the region's languages appear to have absorbed the habit. Old French ran both systems side by side — septante, octante and nonante all existed — and the vigesimal forms happened to prevail in the Parisian standard that became modern French.
Traces of base twenty survive elsewhere. Danish builds its tens on halves of twenties; English preserves "score" in phrases like fourscore. French is unusual only in having kept the arithmetic fully visible in everyday counting.
Practising it
Prices and years are the fastest drill, because they force the awkward range constantly. Read prices aloud in French while shopping, and say years out loud — 1975 is mille neuf cent soixante-quinze, 1998 is mille neuf cent quatre-vingt-dix-huit. A few days of that does more than any amount of staring at the table.
Hear and check French words offline
The free English-French Dictionary carries the full vocabulary with pronunciation guidance, so numbers and everything else are one tap away without a connection.
Open the dictionary appFrequently asked questions
Do Swiss and Belgian French really use different numbers?
Yes, and they are entirely standard there. Belgium and Switzerland use septante for 70 and nonante for 90; Switzerland also uses huitante for 80 in several cantons, while Belgium keeps quatre-vingts. A French speaker from Paris will understand these without difficulty even though they would not say them.
Why does quatre-vingts lose its s in quatre-vingt-un?
The s appears only when quatre-vingts stands as a complete multiple of twenty with nothing following. Once another number follows — quatre-vingt-un, quatre-vingt-dix — the s disappears. The same rule applies to cent: deux cents, but deux cent un.
Where did the base-twenty counting come from?
It is generally attributed to Celtic influence, since Breton and other Celtic languages count in twenties. Old French had both systems in circulation, including septante and nonante, and the vigesimal forms won out in the standard variety while the decimal ones survived regionally.