Decimal fractions (целые, десятые)

In English, we read a number like 7.8 as "seven point eight." In Russian, decimal fractions are written with a comma (запятая), not a dot.

When speaking, Russians explicitly name the "whole" units (целые) at the comma, followed by the fractional unit: "tenths" (десятые), "hundredths" (сотые), or "thousandths" (тысячные).

Gender and Number Agreement

Because decimal numbers imply the feminine noun часть (part), you must use the feminine forms for numbers 1 and 2: одна and две.

The words for the units (целая, десятая, сотая, тысячная) act like adjectives and change their endings based on the last digit of the number preceding them:

• Ends in 1 (except 11): одна целая, одна десятая, одна сотая, одна тысячная
• Ends in 2, 3, or 4 (except 12–14): две/три/четыре
  • целых, десятых, сотых, тысячных
• 0, or ends in 5–9, 11–19: ноль/пять
  • целых, десятых, сотых, тысячных

Reading Tenths (десятые)

Let's apply these rules to numbers with one decimal place. For 7.8, both "seven" and "eight" fall into the categories requiring the plural ending, giving us семь целых восемь десятых. For 0.5, we say ноль целых пять десятых.

Hundredths (сотые) and Thousandths (тысячные)

The exact same agreement rules apply to numbers with more decimal places, which are common in scientific measurements and calculations.

Notice how 3.14 uses сотых (because 14 falls into the 11–19 category), while 0.02 uses the feminine две followed by сотых.

For three decimal places, use thousandths (тысячные). Pay attention to how the ending changes between a number ending in 5 (тысячных) versus a number ending in 1 (тысячная).