php convert datetime to UTC

0 votes
asked Jan 19, 2010 by jeremey

I am in need of an easy way to convert a date time stamp to UTC (from whatever timezone the server is in) HOPEFULLY without using any libraries.

13 Answers

0 votes
answered Jan 14, 2010 by johan

If you have a date in this format YYYY-MM-HH dd:mm:ss, you can actually trick php by adding a UTC at the end of your "datetime string" and use strtotime to convert it.

date_default_timezone_set('Europe/Stockholm');
print date('Y-m-d H:i:s',strtotime("2009-01-01 12:00"." UTC"))."\n";
print date('Y-m-d H:i:s',strtotime("2009-06-01 12:00"." UTC"))."\n";

This will print this:

2009-01-01 13:00:00
2009-06-01 14:00:00

And as you can see it takes care of the daylight savings time problem as well.

A little strange way to solve it.... :)

0 votes
answered Jan 19, 2010 by psychotik

http://php.net/manual/en/function.strtotime.php or if you need to not use a string but time components instead, then http://us.php.net/manual/en/function.mktime.php

0 votes
answered Jan 19, 2010 by poke

Use strtotime to generate a timestamp from the given string (interpreted as local time) and use gmdate to get it as a formatted UTC date back.

Example

As requested, here’s a simple example:

echo gmdate('d.m.Y H:i', strtotime('2012-06-28 23:55'));
0 votes
answered Jan 19, 2010 by phill-pafford

Try the getTimezone and setTimezone, see the example

(But this does use a Class)

UPDATE:

Without any classes you could try something like this:

$the_date = strtotime("2010-01-19 00:00:00");
echo(date_default_timezone_get() . "<br />");
echo(date("Y-d-mTG:i:sz",$the_date) . "<br />");
echo(date_default_timezone_set("UTC") . "<br />");
echo(date("Y-d-mTG:i:sz", $the_date) . "<br />");

NOTE: You might need to set the timezone back to the original as well

0 votes
answered Jan 3, 2011 by attilio

Do this way:

gmdate('Y-m-d H:i:s', $timestamp)

or simply

gmdate('Y-m-d H:i:s')

to get "NOW" in UTC.

Check the reference:

http://www.php.net/manual/en/function.gmdate.php

0 votes
answered Jan 18, 2011 by steviej

try

echo date('F d Y', strtotime('2010-01-19 00:00:00'));

will output:

January 19 2010

you should change format time to see other output

0 votes
answered Jan 9, 2012 by muy-belgium

With PHP 5 or superior, you may use datetime::format function (see documentation http://us.php.net/manual/en/datetime.format.php)

 echo strftime( '%e %B %Y' , 
    date_create_from_format('Y-d-m G:i:s', '2012-04-05 11:55:21')->format('U')
    );  // 4 May 2012
0 votes
answered Jan 16, 2012 by aorcsik

I sometime use this method:

// It is not importnat what timezone your system is set to.
// Get the UTC offset in seconds:
$offset = date("Z");

// Then subtract if from your original timestamp:
$utc_time = date("Y-m-d H:i:s", strtotime($original_time." -".$offset." Seconds"));

Works all MOST of the time.

0 votes
answered Jan 18, 2012 by christos-pontikis

As strtotime requires specific input format, DateTime::createFromFormat could be used (php 5.3+ is required)

// set timezone to user timezone
date_default_timezone_set($str_user_timezone);

// create date object using any given format
$date = DateTime::createFromFormat($str_user_dateformat, $str_user_datetime);

// convert given datetime to safe format for strtotime
$str_user_datetime = $date->format('Y-m-d H:i:s');

// convert to UTC
$str_UTC_datetime = gmdate($str_server_dateformat, strtotime($str_user_datetime));

// return timezone to server default
date_default_timezone_set($str_server_timezone);
0 votes
answered Jan 12, 2014 by joerx

Using DateTime:

$given = new DateTime("2014-12-12 14:18:00");
echo $given->format("Y-m-d H:i:s e") . "\n"; // 2014-12-12 14:18:00 Asia/Bangkok

$given->setTimezone(new DateTimeZone("UTC"));
echo $given->format("Y-m-d H:i:s e") . "\n"; // 2014-12-12 07:18:00 UTC
Welcome to Q&A, where you can ask questions and receive answers from other members of the community.
Website Online Counter

...