Number Grouping Styles by Locale: Indian, Western, and East Asian

Number Grouping Conventions Around the World

While most developers are familiar with the Western convention of grouping digits in threes (1,234,567), other numbering systems use different grouping patterns.

Western Grouping (Groups of 3)

new Intl.NumberFormat('en-US').format(12345678);
// "12,345,678"

new Intl.NumberFormat('de-DE').format(12345678);
// "12.345.678"

new Intl.NumberFormat('fr-FR').format(12345678);
// "12 345 678"

Indian Numbering System (Lakhs and Crores)

In the Indian numbering system, the first group is 3 digits, then groups of 2:

new Intl.NumberFormat('en-IN').format(12345678);
// "1,23,45,678"

new Intl.NumberFormat('hi-IN').format(12345678);
// "1,23,45,678"

This represents: 1 crore, 23 lakh, 45 thousand, 678.

Western	Indian
10,000	10,000
100,000	1,00,000 (1 lakh)
1,000,000	10,00,000 (10 lakh)
10,000,000	1,00,00,000 (1 crore)

East Asian Grouping

Chinese, Japanese, and Korean traditionally group by 10,000 (万):

new Intl.NumberFormat('zh-CN').format(12345678);
// "12,345,678" (uses Western grouping in standard format)

// But compact notation uses 10,000-based grouping:
new Intl.NumberFormat('zh-CN', { notation: 'compact' })
  .format(12345678);  // "1235万"

new Intl.NumberFormat('ja-JP', { notation: 'compact' })
  .format(12345678);  // "1235万"

Controlling Grouping

// No grouping
new Intl.NumberFormat('en-US', { useGrouping: false })
  .format(12345678);  // "12345678"

// Minimum grouping (at least 2 digits in leading group)
new Intl.NumberFormat('en-US', { useGrouping: 'min2' })
  .format(1234);    // "1234" (leading group has only 1 digit)
new Intl.NumberFormat('en-US', { useGrouping: 'min2' })
  .format(12345);   // "12,345"

Separator Characters

Locale	Thousands	Decimal
en-US	, (comma)	. (period)
de-DE	. (period)	, (comma)
fr-FR	(narrow space)	, (comma)
hi-IN	, (comma)	. (period)
ar-SA	٬	٫