Soixante-dix vs. septante
The main difference between the French words soixante-dix and septante primarily lies in the location they are used within Francophone regions. Both translate to seventy in English, but are used in different parts of the French-speaking world.
Soixante-dix
A1Soixante-dix which translates to sixty-ten, is commonly used in France. It is part of a vigesimal (base 20) counting system particular to French.
J'ai soixante-dix ans.
(I am seventy years old.)
Cette maison a coûté soixante-dix mille euros.
(This house cost seventy thousand euros.)
Septante
B1Septante is mostly used in Switzerland and Belgium as a more directly decimal (base 10) expression for seventy, similar to most other Romanic languages.
Il y a septante personnes dans la salle.
(There are seventy people in the room.)
Elle a atteint l'âge de septante ans.
(She has reached the age of seventy.)
Summary
Soixante-dix and septante both denote the number 70 in French, but their usage varies based on regional dialects. Soixante-dix, a remnant of the vigesimal system, is mainly used in France while septante follows a more direct decimal system and is mainly used in Switzerland and Belgium.