As per title: how to convert a string date (YYYY-MM-DD) to epoch (seconds since 01-01-1970) in PHP
Perhaps this answers your question
http://www.epochconverter.com/programming/functions-php.php
Here is the content of the link:
There are many options:
strtotime parses most English language date texts to epoch/Unix Time.
echo strtotime("15 November 2012");
// ... or ...
echo strtotime("2012/11/15");
// ... or ...
echo strtotime("+10 days"); // 10 days from now
It's important to check if the conversion was successful:
// PHP 5.1.0 or higher, earlier versions check: strtotime($string)) === -1
if ((strtotime("this is no date")) === false) {
echo 'failed';
}
2. Using the DateTime class:
The PHP 5 DateTime class is nicer to use:
// object oriented
$date = new DateTime('01/15/2010'); // format: MM/DD/YYYY
echo $date->format('U');
// or procedural
$date = date_create('01/15/2010');
echo date_format($date, 'U');
The date format 'U' converts the date to a UNIX timestamp.
This version is more of a hassle but works on any PHP version.
// PHP 5.1+
date_default_timezone_set('UTC'); // optional
mktime ( $hour, $minute, $second, $month, $day, $year );
// before PHP 5.1
mktime ( $hour, $minute, $second, $month, $day, $year, $is_dst );
// $is_dst : 1 = daylight savings time (DST), 0 = no DST , -1 (default) = auto
// example: generate epoch for Jan 1, 2000 (all PHP versions)
echo mktime(0, 0, 0, 1, 1, 2000);