What is WP_MEMORY_LIMIT in WordPress?

WP_MEMORY_LIMIT is a constant that sets the maximum amount of memory that WordPress should allocate for PHP.

It’s defined under [github_path location=”wp-includes/default-constants.php#L46-L54″ link=”https://github.com/WordPress/WordPress/blob/master/wp-includes/default-constants.php#L46-L54″]

Code

<?php
if ( ! defined( 'WP_MEMORY_LIMIT' ) ) {
	if ( false === wp_is_ini_value_changeable( 'memory_limit' ) ) {
		define( 'WP_MEMORY_LIMIT', $current_limit );
	} elseif ( is_multisite() ) {
		define( 'WP_MEMORY_LIMIT', '64M' );
	} else {
		define( 'WP_MEMORY_LIMIT', '40M' );
	}
}

The default value is 64M for multisite installation and 40M for non-multisite installations.

It can be changed by defining a personalized value in the wp-config.php file.

For more on how to do it, check:

[manual_related_posts ids=”64970″]