Convert time and date from one time zone to another in PHP

try this, it might help :)

function converToTz($time="",$toTz='',$fromTz='')
    {   
        // timezone by php friendly values
        $date = new DateTime($time, new DateTimeZone($fromTz));
        $date->setTimezone(new DateTimeZone($toTz));
        $time= $date->format('Y-m-d H:i:s');
        return $time;
    }

A bit description: The function takes 3 inputs, time to convert, timezone to convert to, current timezone and returns the output in the specified format.

I know its late. For anyone who would want simple function to convert utc to any local time zone

function UTCTimeToLocalTime($time, $tz = '', $FromDateFormat = 'Y-m-d H:i:s', $ToDateFormat = 'Y-m-d H:i:s')
{
if ($tz == '')
    $tz = date_default_timezone_get();

$utc_datetime = DateTime::createFromFormat($FromDateFormat, $time, new
    DateTimeZone('UTC'));
$local_datetime = $utc_datetime;

$local_datetime->setTimeZone(new DateTimeZone($tz));
return $local_datetime->format($ToDateFormat);
}

 echo UTCTimeToLocalTime('2015-07-01 13:30:00','America/Denver');

<?php
$date = new DateTime('2000-01-01', new DateTimeZone('Pacific/Nauru'));
echo $date->format('Y-m-d H:i:sP') . "\n";

$date->setTimezone(new DateTimeZone('Pacific/Chatham'));
echo $date->format('Y-m-d H:i:sP') . "\n";
?>

The above examples will output:

2000-01-01 00:00:00+12:00
2000-01-01 01:45:00+13:45

found on DateTime Manual on php.net

EDIT: Like Pekka said: The DateTime class exists from 5.2 on and there you first have to find out which of the methods are realy implemented and which one only exist from 5.3 on.