How to convert minutes to hours/minutes and add various time values together using jQuery?

There are a couple parts to this question. I am not opposed to using a jQuery plugin if anyone knows of one that will accomplish what I want done.

Q1 - How do I convert minutes into hours and vise versa? For example how would I convert 90 minutes into 1 hour and 30 minutes. In the code below how would I get "totalMin" converted and displayed in "convertedHour" and "convertedMin"?

HTML:

<span class="totalMin">90</span> Minutes

<span class="convertedHour">0</span> Hours
<span class="convertedMin">0</span> Minutes

jsFiddle: http://jsfiddle.net/ExFBD

Q2 - How would I add up a group of time slots? For example, How would I add 1 hour 30 mins, 2 hours 45 mins and 2 hour 15 mins together?

HTML:

<span class="hour-1 hour">1</span> hour
<span class="min-1 min">30</span> min

<span class="hour-2 hour">2</span> hour
<span class="min-2 min">45</span> min

<span class="hour-3 hour">2</span> hour
<span class="min-3 min">15</span> min


<span class="totalHour">0</span> hour
<span class="totalMin">0</span> min

jsFiddle: http://jsfiddle.net/DX9YA/

Q3 - How would I take a time value (3 hours and 30 mins) and add it to a real time stamp such as 10:30 AM? How would I take AM vs PM into account?

Q1:

$(document).ready(function() {
    var totalMinutes = $('.totalMin').html();
    
    var hours = Math.floor(totalMinutes / 60);          
    var minutes = totalMinutes % 60;

    $('.convertedHour').html(hours);
    $('.convertedMin').html(minutes);    
});

Q2:

$(document).ready(function() {
    
    var minutes = 0;
        
    $('.min').each(function() {
        minutes = parseInt($(this).html()) + minutes;
    });
    
    var realmin = minutes % 60
    var hours = Math.floor(minutes / 60)
        
    $('.hour').each(function() {
        hours = parseInt($(this).html()) + hours;
    });
    
                                     
    $('.totalHour').html(hours);
    $('.totalMin').html(realmin);    
    
});

In case you want to return a string in 00:00 format...

convertMinsToHrsMins: function (minutes) {
  var h = Math.floor(minutes / 60);
  var m = minutes % 60;
  h = h < 10 ? '0' + h : h; 
  m = m < 10 ? '0' + m : m; 
  return h + ':' + m;
}

Thanks for the up-votes. Here's a slightly tidier ES6 version :)

const convertMinsToHrsMins = (mins) => {
  let h = Math.floor(mins / 60);
  let m = mins % 60;
  h = h < 10 ? '0' + h : h; // (or alternatively) h = String(h).padStart(2, '0')
  m = m < 10 ? '0' + m : m; // (or alternatively) m = String(m).padStart(2, '0')
  return `${h}:${m}`;
}

The function below will take as input # of minutes and output time in the following format: Hours:minutes. I used Math.trunc(), which is a new method added in 2015. It returns the integral part of a number by removing any fractional digits.

function display(a){
  var hours = Math.trunc(a/60);
  var minutes = a % 60;
  console.log(hours +":"+ minutes);
}

display(120); //"2:0"
display(60); //"1:0:
display(100); //"1:40"
display(126); //"2:6"
display(45); //"0:45"

 Very short code for transferring minutes in two formats!

let format1 = (n) => `${n / 60 ^ 0}:` + n % 60

console.log(format1(135)) // "2:15"
console.log(format1(55)) // "0:55"

let format2 = (n) => `0${n / 60 ^ 0}`.slice(-2) + ':' + ('0' + n % 60).slice(-2)

console.log(format2(135)) // "02:15"
console.log(format2(5)) // "00:05"

var timeConvert = function(n){
 var minutes = n%60
 var hours = (n - minutes) / 60
 console.log(hours + ":" + minutes)
}
timeConvert(65)

this will log 1:5 to the console. It is a short and simple solution that should be easy to understand and no jquery plugin is necessary...

function parseMinutes(x) {
  hours = Math.floor(x / 60);
  minutes = x % 60;
}

function parseHours(H, M) {
  x = M + H * 60;
}

I took the liberty of modifying ConorLuddy's answer to address both 24 hour time and 12 hour time.

function minutesToHHMM (mins, twentyFour = false) {
  let h = Math.floor(mins / 60);
  let m = mins % 60;
  m = m < 10 ? '0' + m : m;
  
  if (twentyFour) {
    h = h < 10 ? '0' + h : h;
    return `${h}:${m}`;
  } else {
    let a = 'am';
    if (h >= 12) a = 'pm';
    if (h > 12) h = h - 12;
    return `${h}:${m} ${a}`;
  }
}

This code can be used with timezone

javascript:

let minToHm = (m) => {
  let h = Math.floor(m / 60);
  h += (h < 0) ? 1 : 0;
  let m2 = Math.abs(m % 60);
  m2 = (m2 < 10) ? '0' + m2 : m2;
  return (h < 0 ? '' : '+') + h + ':' + m2;
}

console.log(minToHm(210)) // "+3:30"
console.log(minToHm(-210)) // "-3:30"
console.log(minToHm(0)) // "+0:00"

minToHm(210)
"+3:30"

minToHm(-210)
"-3:30"

minToHm(0)
"+0:00"

As the above answer of ConnorLuddy can be slightly improved, there is a minor change to formula to convert minutes to hours:mins format

const convertMinsToHrsMins = (mins) => {
  let h = Math.floor(mins / 60);
  let m = Math.round(mins % 60);
  h = (h < 10) ? ('0' + h) : (h);
  m = (m < 10) ? ('0' + m) : (m);
  return `${h}:${m}`;
}

My theory is that we can not predict that mins value will always be an integer.
The added Math.round to function will correct the output.
For example: when the minutes=125.3245, the output will be 02:05 with this fix, and 02:05.3245000000000005 without the fix.

Hope that someone need this!

Not a jquery plugin, but the DateJS Library appears to do what you require. The Getting Started page has a number of examples.

Alternated to support older browsers.

function minutesToHHMM (mins, twentyFour) {
  var h = Math.floor(mins / 60);
  var m = mins % 60;
  m = m < 10 ? '0' + m : m;

  if (twentyFour === 'EU') {
    h = h < 10 ? '0' + h : h;
    return h+':'+m;
  } else {
    var a = 'am';
    if (h >= 12) a = 'pm';
    if (h > 12) h = h - 12;
    return h+':'+m+a;
  }
}