Learn 0–20, the tens, the hundreds, ты́сяча (thousand) and миллио́н (million), then string them together. The noun after a number depends on the last digit: 1 takes the normal form, 2–4 take one form, and 5 and up take another.
1. 0 to 20
The first twenty are the foundation. From 11 to 19, Russian adds -на́дцать (“on ten”) to the single digit, just as English adds “-teen”. Tap any number to hear it.
2. Tens, hundreds and beyond
These are the remaining building blocks. 20 and 30 add -дцать; 50 to 80 add -десят; 40 and 90 are their own words. Hundreds follow a similar pattern.
3. Build any number
Type any number from 0 to 999,999 and see it built from blocks, biggest first, with pronunciation. Watch what happens to ты́сяча (thousand) after 2 and after 5.
4. “One” and “two” change with gender
One behaves like an adjective: it matches the gender of its noun. Two has a masculine/neuter form and a feminine form. All other numbers have one form only.
5. Nouns after numbers: the 1–2–5 rule
This is the most important rule on the page. Look only at the last digit. 1 takes the dictionary form; 2, 3 and 4 take the genitive singular; 5 to 9 and 0 take the genitive plural. Numbers 11 to 14 always take the genitive plural.
6. First, second, third: ordinal numbers
Ordinal numbers show order: first, second, tenth. In Russian they are adjectives, so they take adjective endings and match their noun: пе́рвый день (first day), пе́рвая неде́ля (first week).
7. Numbers in real life
Age, prices and phone numbers each have their own pattern. Notice how the 1–2–5 rule appears in all of them.
8. Collective numbers: дво́е, тро́е, о́ба
For groups of people, and with nouns that only exist in the plural, Russians often use collective numbers. They take the genitive plural.
9. Halves, quarters, decimals and percent
Russian writes a comma for the decimal point: 3,5. Fractions and percent take the genitive.
10. Saying “about” a number
Use о́коло + genitive, or simply put the noun before the number: два часа́ is “two hours”, but часа́ два is “about two hours”.
11. Pick the right ending
Look at the last digit, then choose. Remember 11–14 are special.