Cookie Lifetime in PHP

You already know that cookies must be written using the function setcookie:

<?php
	setcookie('test', 'abcde');
?>

However, such cookies do not live long - only until the browser is closed. You can extend the lifetime of a cookie using the third parameter, which accepts a point in time in the timestamp format. As soon as this moment arrives - the cookie will automatically be deleted by the browser.

However, setting a specific cookie expiration time is not very convenient. It would be more convenient to set a cookie, for example, for an hour from the current time, or for a day, or for a year.

Therefore, the third parameter is usually written like this: current time + N seconds. The current time in timestamp format can be obtained using the function time.

Let's set a cookie for one hour as an example. Since there are 3600 seconds in an hour, let's add this number to the current time:

<?php
	setcookie('test', 'abcde', time() + 3600);
?>

When setting cookies, seconds are usually written in this form: 60 * 60 - this is an hour, 60 * 60 * 24 - this is a day. And so on. This is done so that it is obvious to anyone reading your code for what period of time the cookie is set.

Let's set a cookie for a day as an example:

<?php
	setcookie('test', 'abcde', time() + 60 * 60 * 24);
?>

Set some cookie for a month.

Set some cookie for a year.

Set some cookie for 10 years.