Add 15 minutes to string in javascript

Question

var time="18:15:00"

I am getting time in 24 hour format like above string. i have to add 15 minutes to time how can i add. Without using substring().

var time is string not a date object. Search on google but not get it.

Convert it to a Date, add 15 minutes, convert back to string? — Lars Kotthoff, Jul 03 '13 at 11:17
@alex: Because using string operations to modify dates/times is horrible in the first place. — ThiefMaster, Jul 03 '13 at 11:22
@ThiefMaster It is to *modify*, but it's a useful tool for extracting parts of a date (though `split()` would be my suggestion in this example). — alex, Jul 03 '13 at 11:25
Possible duplicate of http://stackoverflow.com/questions/1197928/how-to-add-30-minutes-to-a-javascript-date-object — Rohan Kumar, Jul 03 '13 at 11:37

Dhaval Marthak · Accepted Answer · 2013-07-03T11:31:34.310

22

You can do like this:

 function addMinutes(time, minsToAdd) {
  function D(J){ return (J<10? '0':'') + J;};
  var piece = time.split(':');
  var mins = piece[0]*60 + +piece[1] + +minsToAdd;

  return D(mins%(24*60)/60 | 0) + ':' + D(mins%60);  
}  

addMinutes('18:15:00', '20');  // '18:35'

DEMO Plunker

edited Jul 03 '13 at 11:31

answered Jul 03 '13 at 11:24

Dhaval Marthak

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Yeah for that simply do like this `var mins = piece[0]*60 + +piece[1] + -minsToAdd;` you can play with plunker – Dhaval Marthak Jul 03 '13 at 12:07
1

@DhavalMarthak or pass -20 instead of 20. – Shah Abaz Khan May 15 '20 at 05:13
Thanks. I was having a hard time trying to get a solution for this – Wahome Aug 25 '23 at 10:00

NoLdman · Answer 2 · 2017-10-25T16:33:56.857

Dhavals answer is very nice, but I prefer simple & single-line code.
Therefore, I'd use following:

var minsToAdd = 15;
var time = "15:57";
var newTime = new Date(new Date("1970/01/01 " + time).getTime() + minsToAdd * 60000).toLocaleTimeString('en-UK', { hour: '2-digit', minute: '2-digit', hour12: false });

(If you need the seconds, just add second: '2-digit' to the formatting options.)

Further Information: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleTimeString

mooga · Answer 3 · 2018-06-14T12:10:59.887

Just convert the Original time string to time then convert added time string to time then add them

  var time="18:15:00"; // Original Time
  var timeToadd = "00:15:00";  // Time to be added in min
  var timeToAddArr = timeToadd.split(":");             
  var ms = (60 * 60 * parseInt(timeToAddArr[0]) + 60 * (parseInt(timeToAddArr[1])) ) * 1000;
  
  var newTime =new Date('1970-01-01T' + time ).getTime() + ms
  var finalTime = new Date(newTime).toLocaleString('en-GB').slice(12 ,20)

  console.log(finalTime)

Add 15 minutes to string in javascript

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