JavaScript Dates and Times

JavaScript Date object is used to work with dates and times. It provides methods for creating, formatting, and manipulating dates and times.

Creating a Date Object

You can create a new Date object in several ways.

This creates a new Date object with the current date and time:

new Date();

This creates a new Date object with a specified number of milliseconds since January 1, 1970, 00:00:00 UTC (the Unix epoch):

new Date(milliseconds);

This creates a new Date object from a string representing a date and time:

new Date(dateString);

This creates a new Date object with the specified date and time.

new Date(year, monthIndex[, day[, hour[, minutes[, seconds[, milliseconds]]]]]);

Examples:

const now = new Date(); // current date and time
const januaryFirst1970 = new Date(0); // Unix epoch
const januaryFirst2000 = new Date("January 1, 2000"); // January 1, 2000
const noonOnJanuaryFirst2000 = new Date(2000, 0, 1, 12); // January 1, 2000 at noon

Formatting Dates

You can format a Date object using its built-in methods:

Date.toDateString()

toDateString() returns the date portion of the Date object as a human-readable string in American English.

const now = new Date();
const dateStr = now.toDateString(); // returns "Thu Mar 03 2023"

Date.toISOString()

toISOString() returns a string in simplified extended ISO format (ISO 8601) representing the Date object in UTC time zone.

const now = new Date();
const isoStr = now.toISOString(); // returns "2023-03-03T07:05:18.774Z"

Date.toLocaleDateString()

toLocaleDateString() returns a string representing the Date object's value in the current time zone using a format appropriate for the current locale.

const now = new Date();
const localeDateStr = now.toLocaleDateString(); // returns localized date string, e.g. "3/3/2023" in the US

Date.toLocaleString()

toLocaleString() returns a string representing the Date object's value in the current time zone using a format appropriate for the current locale.

const now = new Date();
const localeStr = now.toLocaleString(); // returns localized date and time string, e.g. "3/3/2023, 7:05:18 AM" in the US

Date.toLocaleTimeString()

toLocaleTimeString() returns a string representation of the time portion of the date object in the current locale's time zone.

const now = new Date();
console.log(now.toLocaleTimeString()); // "12:00:00 AM" (depending on your local time)

Date.toString()

toString() returns a string representation of the date object in the format specified by the implementation.

const now = new Date();
console.log(now.toString()); // "Fri Mar 03 2023 00:00:00 GMT-0800 (Pacific Standard Time)"

Date.toTimeString()

toTimeString() returns a string representation of the time portion of the date object.

const now = new Date();
console.log(now.toTimeString()); // "00:00:00 GMT-0800 (Pacific Standard Time)"

Date.toUTCString()

toUTCString() returns a string representation of the date object in UTC format.

const now = new Date();
console.log(now.toUTCString()); // "Fri, 03 Mar 2023 08:00:00 GMT"

Date.UTC()

UTC() returns the number of milliseconds since January 1, 1970, 00:00:00 UTC for a date specified in UTC.

const utcTime = Date.UTC(2023, 2, 3, 0, 0, 0);
console.log(new Date(utcTime)); // Fri Mar 03 2023 00:00:00 GMT-0800 (Pacific Standard Time)

Date.toJSON()

toJSON() returns a string representation of the date object in ISO format.

const now = new Date();
console.log(now.toJSON()); // "2023-03-03T00:00:00.000Z"

Date.parse()

parse() parses a string representation of a date and returns the number of milliseconds since January 1, 1970, 00:00:00 UTC.

const dateStr = "2023-03-03T00:00:00.000Z";
console.log(Date.parse(dateStr)); // 1688380800000

Date.valueOf()

valueOf() returns the primitive value of a date object, which is the number of milliseconds since January 1, 1970, 00:00:00 UTC.

const now = new Date();
console.log(now.valueOf()); // 1688380800000

Get Date Method

You can manipulate a Date object using its built-in methods:

Date.now()

now() returns the number of milliseconds elapsed since January 1, 1970 00:00:00 UTC.

const nowInMilliseconds = Date.now();
console.log(nowInMilliseconds); // 1646855326193

Date.getDate()

getDate() returns the day of the month (1-31) for the specified date according to local time.

const now = new Date();
const dayOfMonth = now.getDate(); // returns current day of the month, e.g. 3

Date.getMonth()

getMonth() returns the month (0-11) in the specified date according to local time. Note: January is 0, February is 1, and so on.

const now = new Date();
const month = now.getMonth(); // returns current month, e.g. 2 for March (0-based index)

Date.getFullYear()

getFullYear() returns the year (4 digits for 4-digit years) of the specified date according to local time.

const now = new Date();
const year = now.getFullYear(); // returns current year, e.g. 2023

Date.getHours()

getHours() returns the hour (0-23) in the specified date according to local time.

const now = new Date();
const hours = now.getHours(); // returns current hour, e.g. 7 (24-hour clock)

Date.getMinutes()

getMinutes() returns the minutes (0-59) in the specified date according to local time.

const now = new Date();
const minutes = now.getMinutes(); // returns current minute, e.g. 5

Date.getSeconds()

getSeconds() returns the seconds (0-59) in the specified date according to local time.

const now = new Date();
const seconds = now.getSeconds(); // returns current second, e.g. 18

Date.getMilliseconds()

getMilliseconds() returns the milliseconds (0-999) in the specified date according to local time.

const now = new Date();
const milliseconds = now.getMilliseconds();
console.log(milliseconds); // output: e.g. 346

Date.getTime()

getTime() returns the number of milliseconds since January 1, 1970, 00:00:00 UTC.

const now = new Date();
const time = now.getTime();
console.log(time); // output: e.g. 1678085166266

Date.getTimezoneOffset()

getTimezoneOffset() returns the time-zone offset from UTC, in minutes.

const date = new Date();
const offsetInMinutes = date.getTimezoneOffset();
console.log(offsetInMinutes); // -60 (if your time zone is UTC+1)

Date.getUTCDate()

getUTCDate() returns the day of the month, according to universal time (UTC).

const date = new Date("August 19, 1975 23:15:30 UTC");
const utcDate = date.getUTCDate();
console.log(utcDate); // 19

Date.getUTCDay()

getUTCDay() returns the day of the week, according to universal time (UTC).

const date = new Date("August 19, 1975 23:15:30 UTC");
const utcDay = date.getUTCDay();
console.log(utcDay); // 2 (Tuesday)

Date.getUTCFullYear()

getUTCFullYear() returns the year, according to universal time (UTC).

const date = new Date("August 19, 1975 23:15:30 UTC");
const utcYear = date.getUTCFullYear();
console.log(utcYear); // 1975

Date.getUTCMonth()

getUTCMonth() returns the month, according to universal time (UTC).

const date = new Date("August 19, 1975 23:15:30 UTC");
const utcMonth = date.getUTCMonth();
console.log(utcMonth); // 7 (August)

Date.getUTCHours()

getUTCHours() returns the hour, according to universal time (UTC).

const date = new Date("August 19, 1975 23:15:30 UTC");
const utcHours = date.getUTCHours();
console.log(utcHours); // 23

Date.getUTCMinutes()

getUTCMinutes() returns the minutes, according to universal time (UTC).

const date = new Date("August 19, 1975 23:15:30 UTC");
const utcMinutes = date.getUTCMinutes();
console.log(utcMinutes); // 15

Date.getUTCSeconds()

getUTCSeconds() returns the seconds, according to universal time (UTC).

const date = new Date("August 19, 1975 23:15:30 UTC");
const utcSeconds = date.getUTCSeconds();
console.log(utcSeconds); // 30

Date.getUTCMilliseconds()

getUTCMilliseconds() returns the milliseconds, according to universal time (UTC).

const date = new Date("August 19, 1975 23:15:30.123 UTC");
const utcMilliseconds = date.getUTCMilliseconds();
console.log(utcMilliseconds); // 123

Set Date Method

You can manipulate a Date object using its built-in methods:

Date.setDate()

setDate() sets the day of the month for a specified date according to local time.

const now = new Date();
now.setDate(30); // 2023-03-30T06:53:16.981Z

Date.setMonth()

setMonth() sets the month for a specified date according to local time. Note: January is 0, February is 1, and so on.

const now = new Date();
now.setMonth(2);
console.log(now); // 2023-06-06T07:00:52.208Z

Date.setFullYear()

setFullYear() sets the year (4 digits for 4-digit years) for a specified date according to local time.

const now = new Date();
now.setFullYear(2024); // 2024-03-06T07:01:11.938Z

Date.setHours()

setHours() sets the hour for a specified date according to local time.

const now = new Date();
now.setHours(10); // 2023-03-06T09:01:57.743Z

Date.setMinutes()

setMinutes() sets the minutes for a specified date according to local time.

const now = new Date();
now.setMinutes(58); // 2023-03-06T07:55:42.119Z

Date.setSeconds()

setSeconds() sets the seconds for a specified date according to local time.

const now = new Date();
now.setSeconds(30); // check it yourself

Date.setMilliseconds()

setMilliseconds() sets the milliseconds for a specified date according to local time.

const now = new Date();
now.setMilliseconds(60); // check it yourself

Date.setTime()

setTime() sets the Date object to the time represented by a number of milliseconds since January 1, 1970, 00:00:00 UTC.

const now = new Date();
now.setTime(1678085166300); // check it yourself

Date.setUTCDate()

setUTCDate() - Sets the day of the month (0-31) for a specified date according to universal time.

const date = new Date();
date.setUTCDate(15);
console.log(date.toUTCString()); // output: "Thu, 15 Mar 2023 16:47:56 GMT"

Date.setUTCFullYear()

setUTCFullYear() - Sets the year (optionally month and day) for a specified date according to universal time.

const date = new Date();
date.setUTCFullYear(2024, 11, 31);
console.log(date.toUTCString()); // output: "Wed, 31 Dec 2024 16:47:56 GMT"

Date.setUTCMonth()

setUTCMonth() - Sets the month (0-11) and day of the month (0-31) for a specified date according to universal time.

const date = new Date();
date.setUTCMonth(11, 31);
console.log(date.toUTCString()); // output: "Fri, 31 Jan 2024 16:47:56 GMT"

Date.setUTCHours()

setUTCHours() - Sets the hours (0-23), minutes, seconds, and milliseconds for a specified date according to universal time.

const date = new Date();
date.setUTCHours(12, 30, 45, 500);
console.log(date.toUTCString()); // output: "Thu, 03 Mar 2023 12:30:45 GMT"

Date.setUTCMinutes()

setUTCMinutes() - Sets the minutes (0-59), seconds, and milliseconds for a specified date according to universal time.

const date = new Date();
date.setUTCMinutes(30, 45, 500);
console.log(date.toUTCString()); // output: "Thu, 03 Mar 2023 16:30:45 GMT"

Date.setUTCSeconds()

setUTCSeconds() - Sets the seconds (0-59) and milliseconds for a specified date according to universal time.

const date = new Date();
date.setUTCSeconds(45, 500);
console.log(date.toUTCString()); // output: "Thu, 03 Mar 2023 16:47:45 GMT"

Date.setUTCMilliseconds()

setUTCMilliseconds() - Sets the milliseconds (0-999) for a specified date according to universal time.

const date = new Date();
date.setUTCMilliseconds(500);
console.log(date.toUTCString()); // output: "Thu, 03 Mar 2023 16:47:56 GMT"