I was looking at this post, and it is close to what I need: PHP - How to count 60 days from the add date
However, in that post, the calculation is performed by addi
Use date_add
http://www.php.net/manual/en/datetime.add.php
$my_date = new DateTime($some_row_from_a_database); $date_plus_10_days = date_add($my_date, new DateInterval('P10D'));