100

Back to the basics today - how to count from one to one hundred...
Un = one
Deux = two (the 'x' is silent)
Trois = three (the 's' is silent)
Quatre = four
Cinq = five
Six = Six (pronounced "seess")
Sept = seven (pronounced "set")
Huit = eight
Neuf = nine
Dix = ten (pronounced "deess")
Onze = eleven
Douze = twelve
Treize = thirteen
Quatorze = fourteen
Quinze = fifteen
Seize = sixteen
Dix-sept = seventeen
Dix-huit = eighteen (pronounced "deezuit")
Dix-neuf = nineteen
Vingt = twenty (the 'gt' is silent)

From there on, the construction repeats itself (almost) predictably:
20: vingt-et-un, vingt-deux, vingt-trois, vingt-quatre, vingt-cinq, vingt-six, vingt-sept, vingt-huit, vingt-neuf
30: trente, trente-et-un,...
40: quarante, quarante-et-un,...
50: cinquante, cinquante-et-un,...
60: soixante, soixante-et-un,...
70: continues from 60 in a weird way: soixante-dix, soixante-et-onze, soixante-douze,... (think sixty-ten, sixty-eleven...)
80: quatre-vingt (literally four-twenties), quatre-vingt-un,...
90: probably the weirdest one of all - quatre-vingt-dix (literally four twenties and ten), quatre-vingt-onze,..., quatre-ving-dix-neuf
100: cent (the 't' is silent)