How to get start and end of day in Javascript?

Solution 1:

var start = new Date();
start.setUTCHours(0,0,0,0);

var end = new Date();
end.setUTCHours(23,59,59,999);

alert( start.toUTCString() + ':' + end.toUTCString() );

If you need to get the UTC time from those, you can use UTC().

Solution 2:

With dayjs library, use startOf and endOf methods as follows:

Local GMT:

const start = dayjs().startOf('day'); // set to 12:00 am today
const end = dayjs().endOf('day'); // set to 23:59 pm today

For UTC:

const utc = require('dayjs/plugin/utc');
dayjs.extend(utc);

const start = dayjs.utc().startOf('day'); 
const end = dayjs.utc().endOf('day');

Using the (deprecated) momentjs library, this can be achieved with the startOf() and endOf() methods on the moment's current date object, passing the string 'day' as arguments:

Local GMT:

var start = moment().startOf('day'); // set to 12:00 am today
var end = moment().endOf('day'); // set to 23:59 pm today

For UTC:

var start = moment.utc().startOf('day'); 
var end = moment.utc().endOf('day');

Solution 3:

Using the luxon.js library, same can be achieved using startOf and endOf methods by passing the 'day' as parameter

var DateTime = luxon.DateTime;
DateTime.local().startOf('day').toUTC().toISO(); //2017-11-16T18:30:00.000Z
DateTime.local().endOf('day').toUTC().toISO(); //2017-11-17T18:29:59.999Z
DateTime.fromISO(new Date().toISOString()).startOf('day').toUTC().toISO(); //2017-11-16T18:30:00.000Z

remove .toUTC() if you need only the local time

and you may ask why not moment.js, answer is here for that.

Solution 4:

In MomentJs We can declare it like :

   const start = moment().format('YYYY-MM-DD 00:00:01');
   const end = moment().format('YYYY-MM-DD 23:59:59');

Solution 5:

FYI (merged version of Tvanfosson)

it will return actual date => date when you are calling function

export const today = {
  iso: {
    start: () => new Date(new Date().setHours(0, 0, 0, 0)).toISOString(),
    now: () => new Date().toISOString(),
    end: () => new Date(new Date().setHours(23, 59, 59, 999)).toISOString()
  },
  local: {
  start: () => new Date(new Date(new Date().setHours(0, 0, 0, 0)).toString().split('GMT')[0] + ' UTC').toISOString(),
  now: () => new Date(new Date().toString().split('GMT')[0] + ' UTC').toISOString(),
  end: () => new Date(new Date(new Date().setHours(23, 59, 59, 999)).toString().split('GMT')[0] + ' UTC').toISOString()
  }
}

// how to use

today.local.now(); //"2018-09-07T01:48:48.000Z" BAKU +04:00
today.iso.now(); // "2018-09-06T21:49:00.304Z" *

* it is applicable for Instant time type on Java8 which convert your local time automatically depending on your region.(if you are planning write global app)