How numbers work in Croatian
The numbers 0 to 10 are nula, jedan, dva, tri, četiri, pet, šest, sedam, osam, devet, deset. From 11 to 19 you add -naest: jedanaest, dvanaest, trinaest. Note četrnaest (14), petnaest (15) and šesnaest (16).
The tens end in -deset: dvadeset, trideset, četrdeset, pedeset, šezdeset, sedamdeset, osamdeset, devedeset. The unit follows with or without i (and): dvadeset i jedan or dvadeset jedan. Both are correct; this page uses the form with i.
Among the hundreds, 200 is dvjesto, and from 300 you add -sto: tristo, četiristo, petsto, šesto (600). A thousand is tisuća (tisuću when counting), then dvije tisuće and pet tisuća. A million is milijun. In Serbia and Bosnia people say hiljada and milion.
Jedan and dva agree with the noun: jedan muškarac, jedna žena, jedno dijete; dva grada, dvije kuće. After dva, tri and četiri the noun takes a special form (dva grada); from five it is in the genitive plural (pet gradova).
The ordinals up to ten are prvi, drugi, treći, četvrti, peti, šesti, sedmi, osmi, deveti, deseti. They decline like adjectives.