How do you calculate an end time based on start time and duration?

datetime, duration, php, time

Solution

Using strtotime() you can convert the current time (2009-09-25 15:00:00) to a timestamp and then add (60 * 60 * 3 = 3hrs) to the timestamp. Finally just convert it back to whatever time you want.

//Start date
$date = '2009-09-25 15:00:00';
//plus time
$plus = 60 * 60 * 3;
//Add them
$time = strtotime($date) + $plus;
//Print out new time in whatever format you want
print date("F j, Y, g:i a", $time);

Problem

I'm building a event calendar and pass a start time to PHP, in the format of 2009-09-25 15:00:00. A duration gets passed as well, that might be in the format of 60 minutes or 3 hours. Converting from hours to minutes isn't the problem. How do you add a length of time to an established starting point to correctly format the end time?

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