What is the Intl.NumberFormat API and how is it used?

The Intl.NumberFormat API provides language-sensitive number formatting, allowing you to format numbers according to locale-specific conventions.

     // Basic usage
     const formatter = new Intl.NumberFormat('en-US');
     console.log(formatter.format(1234567.89)); // "1,234,567.89"

     // Different locales
     console.log(new Intl.NumberFormat('de-DE').format(1234567.89));
     // "1.234.567,89"

     console.log(new Intl.NumberFormat('hi-IN').format(1234567.89));
     // "12,34,567.89"
     

Currency formatting:

     const usdFormatter = new Intl.NumberFormat('en-US', {
       style: 'currency',
       currency: 'USD'
     });
     console.log(usdFormatter.format(1234.56)); // "$1,234.56"

     const euroFormatter = new Intl.NumberFormat('de-DE', {
       style: 'currency',
       currency: 'EUR'
     });
     console.log(euroFormatter.format(1234.56)); // "1.234,56 €"
     

Percentage formatting:

     const percentFormatter = new Intl.NumberFormat('en-US', {
       style: 'percent',
       minimumFractionDigits: 2
     });
     console.log(percentFormatter.format(0.1234)); // "12.34%"
     

Unit formatting:

     const distanceFormatter = new Intl.NumberFormat('en-US', {
       style: 'unit',
       unit: 'kilometer',
       unitDisplay: 'long'
     });
     console.log(distanceFormatter.format(50)); // "50 kilometers"
     

Advanced options:

     const formatter = new Intl.NumberFormat('en-US', {
       minimumFractionDigits: 2,
       maximumFractionDigits: 2,
       useGrouping: true
     });
     console.log(formatter.format(1234.5)); // "1,234.50"