Convert a Unix timestamp to time in JavaScript

Question

I am storing time in a MySQL database as a Unix timestamp and that gets sent to some JavaScript code. How would I get just the time out of it?

For example, in HH/MM/

Answer 1

If you want to convert Unix time duration to real hours, minutes, and seconds, you could use the following code:

var hours = Math.floor(timestamp / 60 / 60);
var minutes = Math.floor((timestamp - hours * 60 * 60) / 60);
var seconds = Math.floor(timestamp - hours * 60 * 60 - minutes * 60 );
var duration = hours + ':' + minutes + ':' + seconds;

Answer 2

Code below also provides 3-digit millisecs, ideal for console log prefixes:

const timeStrGet = date => {
    const milliSecsStr = date.getMilliseconds().toString().padStart(3, '0') ;
    return `${date.toLocaleTimeString('it-US')}.${milliSecsStr}`;
};

setInterval(() => console.log(timeStrGet(new Date())), 299);

Answer 3

The problem with the aforementioned solutions is, that if hour, minute or second, has only one digit (i.e. 0-9), the time would be wrong, e.g. it could be 2:3:9, but it should rather be 02:03:09.

According to this page it seems to be a better solution to use Date's "toLocaleTimeString" method.

Answer 4

This works with PHP timestamps

var d = 1541415288860;
//var d =val.timestamp;

//NB: use + before variable name
var date = new Date(+d);

console.log(d);
console.log(date.toDateString());
console.log(date.getFullYear());
console.log(date.getMinutes());
console.log(date.getSeconds());
console.log(date.getHours());
console.log(date.toLocaleTimeString());

var d =val.timestamp;
var date=new Date(+d); //NB: use + before variable name

console.log(d);
console.log(date.toDateString());
console.log(date.getFullYear());
console.log(date.getMinutes());
console.log(date.getSeconds());
console.log(date.getHours());
console.log(date.toLocaleTimeString());

the methods above will generate this results

1541415288860
Mon Nov 05 2018 
2018 
54 
48 
13
1:54:48 PM

There's a bunch of methods that work perfectly with timestamps. Cant list them all

Answer 5

Modern Solution (for 2020)

In the new world, we should be moving towards the standard Intl JavaScript object, that has a handy DateTimeFormat constructor with .format() method:

function format_time(s) {
  const dtFormat = new Intl.DateTimeFormat('en-GB', {
    timeStyle: 'medium',
    timeZone: 'UTC'
  });
  
  return dtFormat.format(new Date(s * 1e3));
}

console.log( format_time(12345) );  // "03:25:45"

---

Eternal Solution

But to be 100% compatible with all legacy JavaScript engines, here is the shortest one-liner solution to format seconds as hh:mm:ss:

function format_time(s) {
  return new Date(s * 1e3).toISOString().slice(-13, -5);
}

console.log( format_time(12345) );  // "03:25:45"

Method Date.prototype.toISOString() returns time in simplified extended ISO 8601 format, which is always 24 or 27 characters long (i.e. YYYY-MM-DDTHH:mm:ss.sssZ or ±YYYYYY-MM-DDTHH:mm:ss.sssZ respectively). The timezone is always zero UTC offset.

This solution does not require any third-party libraries and is supported in all browsers and JavaScript engines.

Answer 6

I'd think about using a library like momentjs.com, that makes this really simple:

Based on a Unix timestamp:

var timestamp = moment.unix(1293683278);
console.log( timestamp.format("HH/mm/ss") );

Based on a MySQL date string:

var now = moment("2010-10-10 12:03:15");
console.log( now.format("HH/mm/ss") );