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I have been fighting with this for a bit now. I’m trying to convert epoch to a date object. The epoch is sent to me in UTC. Whenever you pass new Date() an epoch, it assumes it’s local epoch. I tried creating a UTC object, then using setTime() to adjust it to the proper epoch, but the only method that seems useful is toUTCString() and strings don’t help me. If I pass that string into a new date, it should notice that it’s UTC, but it doesn’t.

new Date( new Date().toUTCString() ).toLocaleString()

My next attempt was to try to get the difference between local current epoch and UTC current epoch, but I wasn’t able to get that either.

new Date( new Date().toUTCString() ).getTime() - new Date().getTime()

It’s only giving me very small differences, under 1000, which is in milliseconds.

Any suggestions?

I have been fighting with this for a bit now. I’m trying to convert epoch to a date object. The epoch is sent to me in UTC. Whenever you pass new Date() an epoch, it assumes it’s local epoch. I tried creating a UTC object, then using setTime() to adjust it to the proper epoch, but the only method that seems useful is toUTCString() and strings don’t help me. If I pass that string into a new date, it should notice that it’s UTC, but it doesn’t.

new Date( new Date().toUTCString() ).toLocaleString()

My next attempt was to try to get the difference between local current epoch and UTC current epoch, but I wasn’t able to get that either.

new Date( new Date().toUTCString() ).getTime() - new Date().getTime()

It’s only giving me very small differences, under 1000, which is in milliseconds.

Any suggestions?

• javascript
• date
• utc
• epoch

Share Improve this question Follow edited Oct 24, 2017 at 10:23 Sebastian Simon 19.5k88 gold badges6060 silver badges8484 bronze badges asked Jan 8, 2011 at 1:59 Shane ReustleShane Reustle 8,95288 gold badges4343 silver badges5252 bronze badges 4

• 17 The epoch time is defined as the elapsed milliseconds since the 1970 date in UTC. There is no such thing as a local epoch! Not sure I understand your problem. – Chetan S Commented Jan 8, 2011 at 2:13
• Maybe the timezone on the computer is incorrect, leading to a different UTC value? – kijin Commented Jan 8, 2011 at 2:25
• 2 You have to set your clock to UTC time, if you want to 'see' UTC time when you use toLocaleString(). Midnight UTC is 7pm EST. If you use new Date().toString() instead of localeString you would get something like: 'Fri Jan 07 2011 07:00:00 GMT-0500 ', which includes the offset. – kennebec Commented Jan 8, 2011 at 3:29
• Epoch unit is seconds, not milliseconds. – Teson Commented Jan 3, 2022 at 9:53

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18 Answers 18

Sorted by: Reset to default 680

I think I have a simpler solution -- set the initial date to the epoch and add UTC units. Say you have a UTC epoch var stored in seconds. How about 1234567890. To convert that to a proper date in the local time zone:

var utcSeconds = 1234567890;
var d = new Date(0); // The 0 there is the key, which sets the date to the epoch
d.setUTCSeconds(utcSeconds);

d is now a date (in my time zone) set to Fri Feb 13 2009 18:31:30 GMT-0500 (EST)

It's easy, new Date() just takes milliseconds, e.g.

new Date(1394104654000)
> Thu Mar 06 2014 06:17:34 GMT-0500 (EST)

Epoch time is in seconds from Jan. 1, 1970. date.getTime() returns milliseconds from Jan. 1, 1970, so.. if you have an epoch timestamp, convert it to a javascript timestamp by multiplying by 1000.

   function epochToJsDate(ts){
        // ts = epoch timestamp
        // returns date obj
        return new Date(ts*1000);
   }

   function jsDateToEpoch(d){
        // d = javascript date obj
        // returns epoch timestamp
        return (d.getTime()-d.getMilliseconds())/1000;
   }

And just for the logs, I did this using Moment.js library, which I was using for formatting anyway.

moment.utc(1234567890000).local()
>Fri Feb 13 2009 19:01:30 GMT-0430 (VET)

 function ToLocalDate (inDate) {
    var date = new Date();
    date.setTime(inDate.valueOf() - 60000 * inDate.getTimezoneOffset());
    return date;
}

Epoch time (i.e. Unix Epoch time) is nearly always the number of seconds that have expired since 1st Jan 1970 00:00:00 (UTC time), not the number of milliseconds which some of the answers here have implied.

https://en.wikipedia.org/wiki/Unix_time

Therefore, if you have been given a Unix Epoch time value it will probably be in seconds, and will look something like 1547035195. If you want to make this human readable in JavaScript, you need to convert the value to milliseconds, and pass that value into the Date(value) constructor, e.g.:

const unixEpochTimeMS = 1547035195 * 1000;
const d = new Date(unixEpochTimeMS);
// Careful, the string output here can vary by implementation...
const strDate = d.toLocaleString();

You don't need to do the d.setUTCMilliseconds(0) step in the accepted answer because the JavaScript Date(value) constructor takes a UTC value in milliseconds (not a local time).

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#Syntax

Also note that you should avoid using the Date(...) constructor that takes a string datetime representation, this is not recommended (see the link above).

var myDate = new Date( your epoch date *1000);

source - https://www.epochconverter.com/programming/#javascript

The Easiest Way

If you have the unix epoch in milliseconds, in my case - 1601209912824

1. convert it into a Date Object as so

const dateObject = new Date(milliseconds)
const humanDateFormat = dateObject.toString() 

output -

Sun Sep 27 2020 18:01:52 GMT+0530 (India Standard Time)

2. if you want the date in UTC -

const dateObject = new Date(milliseconds)
const humanDateFormat = dateObject.toUTCString() 

3. Now you can format it as you please.

To convert the current epoch time in [ms] to a 24-hour time. You might need to specify the option to disable 12-hour format.

$ node.exe -e "var date = new Date(Date.now()); console.log(date.toLocaleString('en-GB', { hour12:false } ));"

2/7/2018, 19:35:24

or as JS:

var date = new Date(Date.now()); 
console.log(date.toLocaleString('en-GB', { hour12:false } ));
// 2/7/2018, 19:35:24

console.log(date.toLocaleString('en-GB', { hour:'numeric', minute:'numeric', second:'numeric', hour12:false } ));
// 19:35:24

Note: The use of en-GB here, is just a (random) choice of a place using the 24 hour format, it is not your timezone!

Addition to the above answer by @djechlin

d = '1394104654000';
new Date(parseInt(d));

converts EPOCH time to human readable date. Just don't forget that type of EPOCH time must be an Integer.

The simplest solution I've found to this, is:

var timestamp = Date.now(), // returns milliseconds since epoch time
    normalisedTime = new Date(timestamp);

Notice this doesn't have the * 1000 at the end of new Date(timestamp) statement as this (for me anyway!) always seems to give out the wrong date, ie instead of giving the year 2019 it gives the year as 51015, so just bear that in mind.

Considering, you have epoch_time available,

// for eg. epoch_time = 1487086694.213
var date = new Date(epoch_time * 1000); // multiply by 1000 for milliseconds
var date_string = date.toLocaleString('en-GB');  // 24 hour format

EDIT

var utcDate = new Date(incomingUTCepoch);
var date = new Date();
date.setUTCDate(utcDate.getDate());
date.setUTCHours(utcDate.getHours());
date.setUTCMonth(utcDate.getMonth());
date.setUTCMinutes(utcDate.getMinutes());
date.setUTCSeconds(utcDate.getSeconds());
date.setUTCMilliseconds(utcDate.getMilliseconds());

EDIT fixed

Are you just asking to convert a UTC string to a "local" string? You could do:

var utc_string = '2011-09-05 20:05:15';
var local_string = (function(dtstr) {
    var t0 = new Date(dtstr);
    var t1 = Date.parse(t0.toUTCString().replace('GMT', ''));
    var t2 = (2 * t0) - t1;
    return new Date(t2).toString();
})(utc_string);

If you prefer to resolve timestamps and dates conversions from and to UTC and local time without libraries like moment.js, take a look at the option below.

For applications that use UTC timestamps, you may need to show the date in the browser considering the local timezone and daylight savings when applicable. Editing a date that is in a different daylight savings time even though in the same timezone can be tricky.

The Number and Date extensions below allow you to show and get dates in the timezone of the timestamps. For example, lets say you are in Vancouver, if you are editing a date in July or in December, it can mean you are editing a date in PST or PDT.

I recommend you to check the Code Snippet down below to test this solution.

Conversions from milliseconds

Number.prototype.toLocalDate = function () {
    var value = new Date(this);

    value.setHours(value.getHours() + (value.getTimezoneOffset() / 60));

    return value;
};

Number.prototype.toUTCDate = function () {
    var value = new Date(this);

    value.setHours(value.getHours() - (value.getTimezoneOffset() / 60));

    return value;
};

Conversions from dates

Date.prototype.getUTCTime = function () {
    return this.getTime() - (this.getTimezoneOffset() * 60000);
};

Usage

// Adds the timezone and daylight savings if applicable
(1499670000000).toLocalDate();

// Eliminates the timezone and daylight savings if applicable
new Date(2017, 6, 10).getUTCTime();

See it for yourself

// Extending Number

Number.prototype.toLocalDate = function () {
    var value = new Date(this);

    value.setHours(value.getHours() + (value.getTimezoneOffset() / 60));

    return value;
};

Number.prototype.toUTCDate = function () {
    var value = new Date(this);

    value.setHours(value.getHours() - (value.getTimezoneOffset() / 60));

    return value;
};

// Extending Date

Date.prototype.getUTCTime = function () {
    return this.getTime() - (this.getTimezoneOffset() * 60000);
};

// Getting the demo to work
document.getElementById('m-to-local-button').addEventListener('click', function () {
  var displayElement = document.getElementById('m-to-local-display'),
      value = document.getElementById('m-to-local').value,
      milliseconds = parseInt(value);
  
  if (typeof milliseconds === 'number')
    displayElement.innerText = (milliseconds).toLocalDate().toISOString();
  else
    displayElement.innerText = 'Set a value';
}, false);

document.getElementById('m-to-utc-button').addEventListener('click', function () {
  var displayElement = document.getElementById('m-to-utc-display'),
      value = document.getElementById('m-to-utc').value,
      milliseconds = parseInt(value);
  
  if (typeof milliseconds === 'number')
    displayElement.innerText = (milliseconds).toUTCDate().toISOString();
  else
    displayElement.innerText = 'Set a value';
}, false);

document.getElementById('date-to-utc-button').addEventListener('click', function () {
  var displayElement = document.getElementById('date-to-utc-display'),
      yearValue = document.getElementById('date-to-utc-year').value || '1970',
      monthValue = document.getElementById('date-to-utc-month').value || '0',
      dayValue = document.getElementById('date-to-utc-day').value || '1',
      hourValue = document.getElementById('date-to-utc-hour').value || '0',
      minuteValue = document.getElementById('date-to-utc-minute').value || '0',
      secondValue = document.getElementById('date-to-utc-second').value || '0',
      year = parseInt(yearValue),
      month = parseInt(monthValue),
      day = parseInt(dayValue),
      hour = parseInt(hourValue),
      minute = parseInt(minuteValue),
      second = parseInt(secondValue);
  
  displayElement.innerText = new Date(year, month, day, hour, minute, second).getUTCTime();
}, false);

<link href="https://cdnjs.cloudflare.com/ajax/libs/semantic-ui/2.2.11/semantic.css" rel="stylesheet"/>

<div class="ui container">
  <p></p>
  
  <h3>Milliseconds to local date</h3>
  <input id="m-to-local" placeholder="Timestamp" value="0" /> <button id="m-to-local-button">Convert</button>
  <em id="m-to-local-display">Set a value</em>

  <h3>Milliseconds to UTC date</h3>
  <input id="m-to-utc" placeholder="Timestamp" value="0" /> <button id="m-to-utc-button">Convert</button>
  <em id="m-to-utc-display">Set a value</em>
  
  <h3>Date to milliseconds in UTC</h3>
  <input id="date-to-utc-year" placeholder="Year" style="width: 4em;" />
  <input id="date-to-utc-month" placeholder="Month" style="width: 4em;" />
  <input id="date-to-utc-day" placeholder="Day" style="width: 4em;" />
  <input id="date-to-utc-hour" placeholder="Hour" style="width: 4em;" />
  <input id="date-to-utc-minute" placeholder="Minute" style="width: 4em;" />
  <input id="date-to-utc-second" placeholder="Second" style="width: 4em;" />
  <button id="date-to-utc-button">Convert</button>
  <em id="date-to-utc-display">Set the values</em>
  
</div>

I have converted the epoch time by using Intl.DateTimeFormat(). The input time is in milliseconds.

here is code example that I used:

let options = {
  year: "numeric",
  month: "numeric",
  day: "numeric",
  hour: "numeric",
  minute: "numeric",
  second: "numeric",
  hour12: false,
  timeZone: Intl.DateTimeFormat().resolvedOptions().timeZone,
};

export const epochTime = (time) => { 
  return new Intl.DateTimeFormat("en-US", options).format(new Date(time)); // returns DD/MM/YYYY hh:mm ss
};

References:

1. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl
2. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat

Simple way to convert Epoch to Specific date format without using Moment

const epochTime = 1697054700000; 
const d = new Date(epochTime);
const date = d.toJSON(); //This will return -->> 2023-10-11T20:05:00.000Z
const date = d.toLocaleDateString(); //This will return -->> 10/24/2023

@Amjad, good idea, but a better implementation would be:

Date.prototype.setUTCTime = function(UTCTimestamp) {
    var UTCDate = new Date(UTCTimestamp);
    this.setUTCFullYear(UTCDate.getFullYear(), UTCDate.getMonth(), UTCDate.getDate());
    this.setUTCHours(UTCDate.getHours(), UTCDate.getMinutes(), UTCDate.getSeconds(), UTCDate.getMilliseconds());
    return this.getTime();
}

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