Useful php date/time formulas.
<?php echo date("Y-m-d"); ?> 2012-02-01 <?php echo date("Y/m/d"); ?> 2012/02/01 <?php echo date("m/d/y"); ?> 02/01/12 ** <?php echo date("M. d, Y"); ?> Feb. 01, 2012 (also, May. 01, 2013 <?php echo date("F d, Y"); ?> February 01, 2012 <?php echo date("D., M. j, Y"); ?> Wed., Feb. 1, 2012 <?php echo date("l, F j, Y"); ?> Wednesday, February 1, 2012 ** <?php echo date("l F d, Y, h:i:s"); ?> Wednesday February 01, 2012, 08:06:03 <?php echo date("l F d, Y, h:i A"); ?> Wednesday February 01, 2012, 08:06 PM <?php date_default_timezone_set('Europe/Copenhagen'); echo 'The time in Copenhagen is: ' . date('H:i:s') . PHP_EOL; ?> The time in Copenhagen is: 09:45:56 <?php date_default_timezone_set('America/New_York'); echo 'The time in New York is: ' . date('H:i:s') . PHP_EOL; ?> The time in New York is: 03:45:56 <?php date_default_timezone_set('Europe/Moscow'); echo 'The time in Moscow is: ' . date('H:i:s') . PHP_EOL; ?> The time in Moscow is: 11:45:56 What if you have users from multiple timezones? Still simple! Ask them what their timezone is and set it accordingly. The function timezone_identifiers_list() gives you an array of all the timezone identifiers, so you can use that to generate a drop down list they can choose from. You can also try out geolocating, but that is beyond the scope of this tutorial. Finally, PHP has a function called gmdate(), which always formats the date in GMT. If you know the offset in seconds you can do like: <?php gmdate('H:i:s', time() + $offset); ?> so you might do <?php gmdate('H:i:s', time() + 3600); ?> (1 hour)