I'd like display dates by week number between giving 2 dates like example below. Is this possible in PHP? if the dates are 2010-12-01 thru 2010-12-19, it will display it as follows. week-1 2010-12-01 2010-12-02 2010-12-03 2010-12-04 2010-12-05 2010-12-06 2010-12-07 week-2 2010-12-08 2010-12-09 2010-12-10 2010-12-11 2010-12-12 2010-12-13 2010-12-14 week-3 2010-12-15 2010-12-16 2010-12-17 2010-12-18 2010-12-19 and so on... I use mysql. It has startdate end enddate fields. thank you in advance. I can get how many weeks in those giving 2 dates and display them using a datediff('ww', '2010-12-01', '2010-12-19', false); I found on the internet. And I can display dates between two dates as follows. But I am having trouble grouping them by week. $sdate = "2010-12-01"; $edate = "2010-12-19"; $days = getDaysInBetween($sdate, $edate); foreach ($days as $val) { echo $val; } function getDaysInBetween($start, $end) { // Vars $day = 86400; // Day in seconds $format = 'Y-m-d'; // Output format (see PHP date funciton) $sTime = strtotime($start); // Start as time $eTime = strtotime($end); // End as time $numDays = round(($eTime - $sTime) / $day) + 1; $days = array(); // Get days for ($d = 0; $d < $numDays; $d++) { $days[] = date($format, ($sTime + ($d * $day))); } // Return days return $days; }