How are Russian ordinals formed?

Russian ordinals are adjectives, so only the final word of a compound ordinal declines while the earlier words stay as cardinals. For example двадцать первый declines as двадцать первого, with двадцать unchanged and only первый taking the adjective ending.

Russian adjectives agree with their noun in case (six of them), gender (three in the singular), and number. That gives a full grid of endings, and the right one depends entirely on the noun, so the tool lets you select each axis.

How does третий differ from первый?

Третий belongs to the soft (possessive-style) adjective declension, with endings like третьего and третьему, while первый and most others use the hard adjective pattern (первого, первому). The tool stores третий separately to get its soft endings right.

What about animacy in the accusative?

In the masculine singular and the plural, the accusative copies the genitive for animate nouns and the nominative for inanimate ones. The tool shows the inanimate accusative by default, since most counted things are inanimate; use the genitive form when the noun is animate.

Is my input sent anywhere?

No. The ordinal stems and ending tables are bundled into the page and all declension runs in your browser. Nothing you enter is uploaded, so your text stays private.

Russian Ordinal Words

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The Russian Ordinal Words tool converts a number into its ordinal adjective and declines it across the full grammatical grid. Russian ordinals behave like adjectives: they agree with their noun in case, gender, and number, and in a compound ordinal only the last word changes — двадцать первого keeps двадцать fixed while первый takes the genitive ending.

How it works

Ordinal stem. The tool builds the ordinal from the number, using a fixed list for irregular stems (первый, второй, третий, четвёртый, …) and the round-number ordinals (десятый, двадцатый, сотый, тысячный). In a compound, leading words stay cardinal and only the final element becomes the ordinal.
Declension pattern. Most ordinals follow the hard adjective declension (первый, первого, первому, первым, о первом). The ordinal третий uses the soft pattern (третьего, третьему, третьем), so it is handled separately.
Agreement axes. You pick case (nominative, genitive, dative, accusative, instrumental, prepositional), gender (masculine, feminine, neuter) in the singular, or the plural, and the tool selects the matching ending.

Tips and notes

Only the last word of a compound ordinal declines. 2026 as a genitive masculine is две тысячи двадцать шестого — the leading parts stay put.
The accusative shown is the inanimate form; for an animate masculine or plural noun, use the genitive instead (the classic animacy rule).
Gender selection applies only in the singular; in the plural a single set of endings serves all genders.