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convert minutes to DD:HH:MM (not a date) [duplicate]

This question already has answers here:
Convert seconds to days, hours, minutes and seconds
(12 answers)
Closed 2 years ago.
I have tried different functions I found in SO but none give me a precise output.
I did one variant of this (adding days and changing to d:h:m)
const convertMinsToHrsMins = (mins) => {
let h = Math.floor(mins / 60);
let m = mins % 60;
h = h < 10 ? '0' + h : h;
m = m < 10 ? '0' + m : m;
return `${h}:${m}`;
}
my last attempt:
// Convert Minutes to Days Hours Minutes
const convertMinutes = (totalMinutes) => {
let Days = Math.floor((totalMinutes / 1440) % 60)
let Hours = Math.floor(totalMinutes / 60)
let Minutes = Math.round(totalMinutes % 60)
let ret = ''
if (Days > 0) {
ret += '' + Days + 'd ' + (Hours < 10 ? '0' : '')
}
ret += '' + Hours + 'h ' + (Minutes < 10 ? '0' : '')
ret += '' + Minutes + 'm'
return ret
}
totalMinutes receive a sum of different inputs(all in minutes!). I need this function to work as close as precise as possible. e.g.: convertMinutes(totalminutes)
937d 23h 59m 8d 00h 01m

Convert 1 day, 1 hour and 1 minute into minutes; subtract one day from your input till you can't anymore; then subtract one hour from your input till you can't anymore; then subtract one minute from your input till you can't anymore or either return the rest. You have to respect that order. Here is a function that mets your necessity:
function converter(minutes)
{
dates=[1440,60,1]
output=[0,0,0];
for(x=0; x<3; x++)
{
while(minutes>=dates[x])
{
minutes-=dates[x]
output[x]++
}
}
return output[0]+"Days;"+output[1]+"Hours;"+output[2]+"Minutes."
}

Use division to get the days, then use modulo to get the remaining minutes which don't sum up to a full day. Use the remaining minutes and and do the same with hours (division and modulo).
const convertMinutes = (totalMinutes) => {
const minutesInDay = 24 * 60;
const minutesInHour = 60;
let days = Math.floor(totalMinutes / minutesInDay);
let remainingMinutes = totalMinutes % minutesInDay;
let hours = Math.floor(remainingMinutes / minutesInHour);
let minutes = remainingMinutes % minutesInHour;
return `${days}d:${hours}h:${minutes}`;
}

How to add hours to string formatted as HH:MM:SS in 24 hour format

I'm trying to add hours to time in the format of 24 hours say '23:59:59'. I need to add, for example, 2.5 hours so the time should roll to the next day and be shown as '02:30:00'.
What I have tried so far works until it reaches '23:59:59'. I need to show the next day time if it exceeds '23:59:59'. Here is what I have tried so far:
var time = $('#starttime').val().split(':');
var d = new Date();
d.setHours(+time[0]);
d.setMinutes(time[1]);
d.setSeconds(time[2]);
var time2 = $('#endtime').val().split(':');
var endtimeval = new Date();
endtimeval.setHours(+time2[0]);
endtimeval.setMinutes(time2[1]);
endtimeval.setSeconds(time2[2]);
var str = d.getHours() + parseInt($('#noofhours').val()) + ":" + time2[1] + ":" + time2[2];
$('#endtime').val(str);

Using a Date Object here is possibly unnecessary, modulo arithmetic should suffice.
const pad = n => {
const s = String(n);
return s.length > 1 ? s : '0' + s;
};
const addHours = (timeVal, numHours) => {
const [hr, min, sec] = timeVal.split(':').map(Number);
const [,lefty, righty] = String(numHours).match(/(\d+)(?:(\.\d+))?/).map(Number);
const hours = (hr + lefty) % 24;
const minutes = righty === undefined ?
min :
((righty * 60 | 0) + min) % 60;
return [hours, minutes, sec].map(pad).join(':');
};
addHours('23:59:59', 2.5) // "01:29:59"
Note that since there's no dates involved it will not accurately handle e.g. daylight savings time. Also note that minutes are in this example rounded down, you could repeat the logic for seconds if desired.
Note that your approach using Date objects will give different answers for the same inputs depending on when/where the logic runs, for the same reasons.

Make a custom date adder?
const add = (time, hours) => {
let [hh, mm, ss] = time.split(':');
const seconds = hours * 60 * 60;
ss = ss * 1 + seconds;
if (ss >= 60) {
mm = mm * 1 + ss / 60;
ss = (ss % 60).toPrecision(2).padStart(2, '0');
}
if (mm >= 60) {
hh = hh * 1 + mm / 60;
mm = (mm % 60).toPrecision(2).padStart(2, '0');
}
hh = (Math.floor(hh) % 24).toString().padStart(2, '0');
return hh + ':' + mm + ':' + ss;
}
console.log(add("23:59:59", 2.5));
you may apply DRY principle and refactor the code yourself. But it will get the job done according to your requirement.

The simple trick that I did is just converted the hours entered as float/int to a minute value by multiplying to 60 and created a date, with this just added the time I already have.
Here the solution with minimal steps:
var time = $('#endtime').val().split(':');
var d = new Date();
d.setHours(+time[0]);
d.setMinutes(time[1]);
d.setSeconds(time[2]);
var addeddate = new Date();
addeddate.setMinutes(parseFloat($('#noofhours').val()) * 60);
$('#endtime').val(("0" + (addeddate.getHours())).slice(-2) + ":" + ("0" + (addeddate.getMinutes())).slice(-2) + ":" + ("0" + (addeddate.getSeconds())).slice(-2)); //The answer that I needed in endtime id value.

You can use vanilla JavaScript Date methods fairly easily here. Most of the work is parsing the time string inputs and then concatenating the time string output. For example:
const start = '23:59:59';
const add = '2.5';
const [hh, mm, ss] = start.split(':').map(x => parseInt(x));
const d = new Date(new Date().setHours(hh, mm + (add * 60), ss));
const end = `${d.getHours()}:${d.getMinutes()}:${d.getSeconds()}`;
console.log(end);
// 2:29:59

Converting Float to Time in Javascript

I am having a three String or Float values say 9.30, 8.00 and 0.40 as Total_hour, Paid_hour, Extra_hour
These should be actually 9 hours 30 minutes, 8 hours 0 minutes, 0 hours 40 minutes.
Question 1) How to convert 9.30 to 9 hours 30 minutes
Question 2) Later want to Subtract and get Remaining Hour = Total_hour-Paid_Hour-Extra_hour
Later the answer Remaining Hour should be in float

This should work.
You just need to convert to ms:
let timefloat = 9.3;
function convertToMs(timefloat) {
// Get the minutes portion
let remainder = timefloat % 1;
// Convert into ms
let minutes = remainder * 100 * 60 * 1000;
// Get the number of hours and convert to ms
let hours = (timefloat - remainder) * 60 * 60 * 1000;
return minutes + hours;
}
// Convert back to float format
function convertToFloat(date) {
let hours = date.getUTCHours();
let mins = date.getUTCMinutes();
return hours + (mins / 100);
}
// Log the result
console.log(new Date(convertToMs(9.3)).toUTCString());
console.log(new Date(convertToMs(8.0)).toUTCString());
console.log(new Date(convertToMs(9.3) - convertToMs(8.0)).toUTCString());
let diff = convertToMs(9.3) - convertToMs(8.0);
console.log(convertToFloat(new Date(diff)))

The following javascript snippet converts a given float to hours and minutes. Source float to time
function convertNumToTime(number) {
// Check sign of given number
var sign = (number >= 0) ? 1 : -1;
// Set positive value of number of sign negative
number = number * sign;
// Separate the int from the decimal part
var hour = Math.floor(number);
var decpart = number - hour;
var min = 1 / 60;
// Round to nearest minute
decpart = min * Math.round(decpart / min);
var minute = Math.floor(decpart * 60) + '';
// Add padding if need
if (minute.length < 2) {
minute = '0' + minute;
}
// Add Sign in final result
sign = sign == 1 ? '' : '-';
// Concate hours and minutes
time = sign + hour + ':' + minute;
return time;
}
console.log(convertNumToTime(11.15));
Output
11:09

First convert the number in minutes and then do your subtraction. Then convert your output to hours.
var Total_hour = '9.30',
Paid_hour = '8.00',
Extra_hour = '0.40';
var conversionInMinutes = hour => Math.floor(hour) * 60 + (hour - (Math.floor(hour))) * 100;
var conversionInHours = min => Math.floor( min/60 ) + min % 60 / 100;
var Remaining_hour = conversionInMinutes(Total_hour) - conversionInMinutes(Paid_hour) - conversionInMinutes(Extra_hour);
console.log(conversionInHours(Remaining_hour).toFixed(2));

function doTime(input)
{
input = input.toString()
inputs = input.split(".")
return (inputs[0] + "Hour and" + inputs[1] + "minutes")
}
doTime("9:22")
function substract2
function subtract2(a , b){
a = input.toString()
arrayA = input.split(".")
b = input.toString()
arrayB = input.split(".")
h = parseInt(arrayB[0]) - parseInt(arrayA[0])
h <0 ? h+=12/*or 24*/ :h=h
m = parseInt(arrayB[1]) - parseInt(arrayA[1])
if(m<0){h-- ; m+=60}
return h.toString() + ":" + m.toString()
}

How to round time to the nearest quarter hour in JavaScript?

For example:
Given time: 08:22 => Rounded to: 08:15
Given time: 08:23 => Rounded to: 08:30
Should be pretty simple. But all I was able to produce is lengthy, not very good code to solve the issue. My mind's just gone blank.
Regards

Given that you have hours and minutes in variables (if you don't you can get them from the Date instance anyway by using Date instance functions):
var m = (parseInt((minutes + 7.5)/15) * 15) % 60;
var h = minutes > 52 ? (hours === 23 ? 0 : ++hours) : hours;
minutes can as well be calculated by using Math.round():
var m = (Math.round(minutes/15) * 15) % 60;
or doing it in a more javascript-sophisticated expression without any functions:
var m = (((minutes + 7.5)/15 | 0) * 15) % 60;
var h = ((((minutes/105) + .5) | 0) + hours) % 24;
You can check the jsPerf test that shows Math.round() is the slowest of the three while mainly the last one being the fastest as it's just an expression without any function calls (no function call overhead i.e. stack manipulation, although native functions may be treated differently in Javascript VM).
//----

This function round the time to the nearest quarter hour.
function roundTimeQuarterHour(time) {
var timeToReturn = new Date(time);
timeToReturn.setMilliseconds(Math.round(timeToReturn.getMilliseconds() / 1000) * 1000);
timeToReturn.setSeconds(Math.round(timeToReturn.getSeconds() / 60) * 60);
timeToReturn.setMinutes(Math.round(timeToReturn.getMinutes() / 15) * 15);
return timeToReturn;
}

With Time String
Here is a method that will round a time string like the one you presented. Eg "08:22"
let roundTime = (time, minutesToRound) => {
let [hours, minutes] = time.split(':');
hours = parseInt(hours);
minutes = parseInt(minutes);
// Convert hours and minutes to time in minutes
time = (hours * 60) + minutes;
let rounded = Math.round(time / minutesToRound) * minutesToRound;
let rHr = ''+Math.floor(rounded / 60)
let rMin = ''+ rounded % 60
return rHr.padStart(2, '0')+':'+rMin.padStart(2, '0')
}
// USAGE //
// Round time to 15 minutes
roundTime('8:07', 15); // "08:00"
roundTime('7:53', 15); // "08:00"
roundTime('7:52', 15); // "07:45"
With Hours and Minutes Already Split Up
You can use this method if you don't need to parse out the hour and minute strings like your example shows
let roundTime = (hours, minutes, minutesToRound) => {
// Convert hours and minutes to minutes
time = (hours * 60) + minutes;
let rounded = Math.round(time / minutesToRound) * minutesToRound;
let roundedHours = Math.floor(rounded / 60)
let roundedMinutes = rounded % 60
return { hours: roundedHours, minutes: roundedMinutes }
}
// USAGE //
// Round time to 15 minutes
roundTime(7, 52, 15); // {hours: 7, minutes: 45}
roundTime(7, 53, 15); // {hours: 8, minutes: 0}
roundTime(1, 10, 15); // {hours: 1, minutes: 15}
With Existing Date Object
Or, if you are looking to round an already existing date object to the nearest x minutes, you can use this method.
If you don't give it any date it will round the current time. In your case, you can round to the nearest 15 minutes.
let getRoundedDate = (minutes, d=new Date()) => {
let ms = 1000 * 60 * minutes; // convert minutes to ms
let roundedDate = new Date(Math.round(d.getTime() / ms) * ms);
return roundedDate
}
// USAGE //
// Round existing date to 5 minutes
getRoundedDate(15, new Date()); // 2018-01-26T00:45:00.000Z
// Get current time rounded to 30 minutes
getRoundedDate(30); // 2018-01-26T00:30:00.000Z

The code here is a little verbose but I'm sure you'll see how you could combine the lines to make this shorter. I've left it this way to clearly show the steps:
var now = new Date();
var mins = now.getMinutes();
var quarterHours = Math.round(mins/15);
if (quarterHours == 4)
{
now.setHours(now.getHours()+1);
}
var rounded = (quarterHours*15)%60;
now.setMinutes(rounded);
document.write(now);

Divide by 9e5 milliseconds (15 * 60 * 1000), round, and multiply back by 9e5 :
const roundToQuarter = date => new Date(Math.round(date / 9e5) * 9e5)
console.log( roundToQuarter(new Date("1999-12-31T23:52:29.999Z")) ) // 1999-12-31T23:45:00
console.log( roundToQuarter(new Date("1999-12-31T23:52:30.000Z")) ) // 2000-01-01T00:00:00
console.log( roundToQuarter(new Date) )

I use these code:
function RoundUp(intervalMilliseconds, datetime){
datetime = datetime || new Date();
var modTicks = datetime.getTime() % intervalMilliseconds;
var delta = modTicks === 0 ? 0 : datetime.getTime() - modTicks;
delta += intervalMilliseconds;
return new Date(delta);
}
function RoundDown(intervalMilliseconds, datetime){
datetime = datetime || new Date();
var modTicks = datetime.getTime() % intervalMilliseconds;
var delta = modTicks === 0 ? 0 : datetime.getTime() - modTicks;
return new Date(delta);
}
function Round(intervalMilliseconds, datetime){
datetime = datetime || new Date();
var modTicks = datetime.getTime() % intervalMilliseconds;
var delta = modTicks === 0 ? 0 : datetime.getTime() - modTicks;
var shouldRoundUp = modTicks > intervalMilliseconds/2;
delta += shouldRoundUp ? intervalMilliseconds : 0;
return new Date(delta);
}
Round to the nearest 5 minutes:
//with current datetime
var result = Round(5 * 60 * 1000);
//with a given datetime
var dt = new Date();
var result = Round(5 * 60 * 1000, dt);

There is an NPM package #qc/date-round that can be used. Given that you have a Date instance to be rounded
import { round } from '#qc/date-round'
const dateIn = ...; // The date to be rounded
const interval = 15 * 60 * 1000; // 15 minutes (aka quarter hour)
const dateOut = round(dateIn, interval)
Then you can use date-fns to format the date
import format from 'date-fns/format';
console.log(format(dateOut, 'HH:mm')) // 24-hr
console.log(format(dateOut, 'hh:mm a')) // 12-hr

Another one with date-fns (not mandatory)
import {getMinutes, setMinutes, setSeconds, setMilliseconds} from 'date-fns'
let date = new Date();
let min = getMinutes(date);
let interval = 3 // in minutes
let new_min = min - min%interval + interval;
let new_date = setMilliseconds(setSeconds(setMinutes(date,new_min),0),0)
console.log('Orignal Date : ' + date);
console.log('Original Minute : ' + min);
console.log('New Minute : ' + new_min);
console.log('New Date : ' + new_date);

Pass the interval in milliseconds get the next cycle in roundUp order
Example if I want next 15 minute cycle from current time then call this method like *calculateNextCycle(15 * 60 * 1000);*
Samething for quarter hour pass the interval
function calculateNextCycle(interval) {
const timeStampCurrentOrOldDate = Date.now();
const timeStampStartOfDay = new Date().setHours(0, 0, 0, 0);
const timeDiff = timeStampCurrentOrOldDate - timeStampStartOfDay;
const mod = Math.ceil(timeDiff / interval);
return new Date(timeStampStartOfDay + (mod * interval));
}
console.log(calculateNextCycle(15 * 60 * 1000));

This method is specifically for Vue.js, it takes a time, and returns to the nearest entered increment, I based this on an above answer, but this is for Vue specifically using echma-6 standards. It will return T:06:00:00, if you fed 06:05 into it. This is used specifically with vuetify's v-calendar to choose a time in weeklyor daily format.
This answer also adds the 0 for like 06 hrs. Which is where this differs from the above answers. If you change the 30 to 15
methods: {
roundTimeAndFormat(datetime, roundTo) {
const hrsMins = datetime.split(':')
let min = ((((hrsMins[1] + 7.5) / roundTo) | 0) * roundTo) % 60
let hr = (((hrsMins[1] / 105 + 0.5) | 0) + hrsMins[0]) % 24
if (Number(hr) < 10) {
hr = ('0' + hr).slice(-2)
}
if (min === 0) {
min = ('0' + min).slice(-2)
}
return 'T' + hr + ':' + min + ':00'
}
}
You would just call:
this.roundTimeAndFormat(dateTime, 15)
And you would get the time to the nearest 15min interval.
If you enter, 11:01, you'd get T11:00:00

Might help others. For any language. Mainly trick with round function.
roundedMinutes = yourRoundFun(Minutes / interval) * interval
E.g. The interval could be 5 minutes, 10 minutes, 15 minutes, 30 minutes.
Then rounded minutes can be reset to the respective date.
yourDateObj.setMinutes(0)
yourDateObj.setMinutes(roundedMinutes)
also if required then
yourDateObj.setSeconds(0)
yourDateObj.setMilliSeconds(0)
Simple?

Javascript: How to turn the time (stored as a fraction) into a readable string?

I have the time stored as a fraction (done so it can be displayed on a graph), e.g. 15.5 is 3.30pm and 23.25 is 11.15pm. I need to turn those numbers into strings in the format HH:MM:SS. Is there a simple way of doing this?

var fraction = 23.5;
var date = new Date(2000, 1, 1); // use any date as base reference
date.setUTCSeconds(fraction * 3600); // add number of seconds in fractional hours
Then use a date formatting script such as this, or Date.js if you're not fond or formatting and padding.
date.format("HH:MM:ss"); // 23:30:00
See an example. I'm using the formatting function from here.

Something like this ?
var fraction = 14.5;
var hours = Math.floor(fraction); // extract the hours (in 24 hour format)
var mins = 60 * (fraction - hours); // calculate the minutes
t = new Date(); // create a date/time object
t.setHours(hours); // set the hours
t.setMinutes(mins); // set the mins
console.log(t.toTimeString()); //show it
or completely manual
var fraction = 14.5;
var hours = Math.floor(fraction);
var mins = 60 * (fraction - hours);
var ampm = ((fraction % 24) < 12) ? 'am' : 'pm';
formatted = ('0' + hours % 12).substr(-2) + ':' + ('0' + mins).substr(-2) + ':00 ' + ampm;
console.log(formatted);
Update
And a version with seconds as well..
var fraction = 14.33;
var hours = Math.floor(fraction);
var allseconds = 3600 * (fraction - hours);
var minutes = Math.floor(allseconds / 60);
var seconds = Math.floor(allseconds % 60);
var ampm = ((fraction % 24) < 12) ? 'am' : 'pm';
formatted = ('0' + hours % 12).substr(-2) + ':' + ('0' + minutes).substr(-2) + ':' + ('0' + seconds).substr(-2) + ' ' + ampm;
console.log(formatted);

Manual function:
var time = function(num) {
if(num < 0 || num >= 24) {throw "Invalid number");}
var x = num > 13 ? num - 12 : num;
var h = Math.floor(x);
var min = x - h;
var ampm = num >= 12 && num < 24 ? "pm" : "am";
return (h + ":" + Math.floor(min * 60) + ampm);
};
Tests:
time(13.40); // 1:24pm
time(11.25); // 11:15pm
time(12.50); // 12:30pm
time(23.50); // 11:30pm
time(0.50); // 0:30am
time(24.00); // error!!