Formatting Dates in JavaScript: Complete Guide

JavaScript offers three ways to turn a Date object into a readable string. toLocaleDateString handles locale-aware display for users. toISOString produces machine-friendly UTC strings for storage. Manual formatting with get methods gives you full control over every character in the output.

javascript

const date = new Date(2026, 6, 14, 14, 30, 0);
 
console.log(date.toLocaleDateString("en-US"));
console.log(date.toISOString().slice(0, 10));

The first prints "7/14/2026" in US format. The second prints "2026-07-14" by slicing just the date portion from the ISO string.

For the fundamentals of creating and reading dates, see the JavaScript Date object guide. For raw timestamp work, see the guide to working with timestamps.

Locale-aware formatting

toLocaleDateString formats a date for a specific locale. Pass a locale string like "en-US" or "de-DE" to control the output.

javascript

const date = new Date(2026, 6, 14);
 
console.log(date.toLocaleDateString("en-US"));
console.log(date.toLocaleDateString("de-DE"));

US English prints "7/14/2026". German prints "14.7.2026". The same date renders in each locale's conventional format without you writing any formatting logic.

For richer output, pass an options object as the second argument. You can include the weekday, control month length, and specify numeric vs long representations.

javascript

const options = { weekday: "long", year: "numeric", month: "long", day: "numeric" };
 
console.log(date.toLocaleDateString("en-US", options));

This prints "Tuesday, July 14, 2026". Available options include weekday, year, month, day, hour, minute, second, and timeZoneName. Each accepts values like "long", "short", "narrow", or "numeric".

The related method toLocaleString adds the time portion to the output.

Machine-readable formatting

toISOString returns a UTC-based ISO 8601 string. This is the format for databases, APIs, and JSON serialization because it is universally parseable and sorts correctly as a string.

javascript

const now = new Date();
console.log(now.toISOString());

This prints "2026-07-14T18:30:00.000Z". The Z suffix means UTC time. For just the date portion, slice the first 10 characters. For a timestamp in milliseconds, use getTime or Date.now instead.

Manual formatting

When locale methods cannot produce the exact format you need, build the string from individual date components. Use getFullYear, getMonth (plus 1), and getDate.

javascript

function formatDate(date) {
  const y = date.getFullYear();
  const m = String(date.getMonth() + 1).padStart(2, "0");
  const d = String(date.getDate()).padStart(2, "0");
  return `${y}-${m}-${d}`;
}
 
console.log(formatDate(new Date(2026, 0, 5)));

This prints "2026-01-05". The padStart calls ensure January (month 0 + 1 = 1) becomes "01" and the 5th becomes "05". Without padding, you would get "2026-1-5".

For a readable format like "Jul 14, 2026", use an array of abbreviated month names indexed by getMonth. Since getMonth returns 0 for January and the array is zero-indexed, no adjustment is needed.

Common mistakes

Forgetting to add 1 to getMonth is the most frequent date formatting bug. getMonth returns 0 for January through 11 for December. Always write date.getMonth() + 1 in display code.

Assuming toISOString returns local time is incorrect. It always returns UTC. If you need a local-time ISO-like string, build it manually with the local get methods.

Using toLocaleDateString without an explicit locale argument produces different output on different machines. Specify a locale when consistency matters across environments.

For parsing JSON date strings back into Date objects, see the guide to JSON parse and stringify.