Polish ordinal numbers answer the question który? (which one?) and behave like adjectives, so they change their ending depending on the gender of the noun they describe. This tool spells any ordinal from 1 to 1000 and shows the masculine, feminine and neuter nominative forms side by side.
How it works
The number is broken into hundreds, tens and units. Each part has its own ordinal stem — for example dwudziesty for 20 and pierwszy for 1. Unlike cardinals, where only the final word may inflect, Polish nominative ordinals inflect every component, so 21 is dwudziesty pierwszy.
The gender ending is applied to each masculine stem:
masculine: -y or -i (pierwszy, trzeci)
feminine: -a (pierwsza, trzecia)
neuter: -e (pierwsze, trzecie)
Stems ending in -i (like drugi, trzeci) and stems ending in -y both drop their final vowel and add -a or -e for the feminine and neuter.
Example and notes
1 gives pierwszy / pierwsza / pierwsze. 21 gives dwudziesty pierwszy (masculine). 100 is setny, and 1000 is tysięczny. Use the feminine form for dates such as the first of May (pierwszego maja, where the genitive ending is a further step) and the neuter form when the ordinal qualifies a neuter noun like miejsce (place).