How do you format a date for a specific locale without a library?

Intermediate

Answer

Intl.DateTimeFormat lets you format dates according to locale conventions and customizable options (weekday, month style, etc.), without needing an external date library for basic formatting.

const formatter = new Intl.DateTimeFormat('en-GB', { dateStyle: 'long' });
console.log(formatter.format(new Date())); // '8 August 2026'

Real-world example Displaying order dates in the format users in a specific country expect (DD/MM/YYYY vs MM/DD/YYYY).

Common follow-ups: How would you format just the time portion, not the date?

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All 10 Date, Time & Internationalization (Intl API) questions