WP Debug Toolkit (WPDT) displays your site’s PHP configuration values and lets you adjust certain WordPress-level limits from the admin dashboard. These settings interact with server-level PHP directives, so WPDT also shows the effective runtime values to help you understand what your site is actually using.
WP_MEMORY_LIMIT sets the maximum amount of memory PHP can allocate for WordPress operations. WordPress defaults to 40 MB on single-site installations and 64 MB on multisite. Most production sites need more than these defaults.
Go to Debug Toolkit > Settings > PHP Settings > Memory Limit. Enter a value in megabytes. WPDT writes or updates the WP_MEMORY_LIMIT constant in wp-config.php:
define( 'WP_MEMORY_LIMIT', '256M' );Common values:
| Value | Use case |
|---|---|
128M | Small sites with lightweight plugins |
256M | Most production sites, WooCommerce stores |
512M | Large sites, complex page builders, bulk operations |
WP_MEMORY_LIMIT cannot exceed the server’s memory_limit directive in php.ini. If php.ini sets memory_limit to 128M, setting WP_MEMORY_LIMIT to 256M has no effect — PHP enforces its own ceiling. WPDT displays both the configured WordPress value and the actual PHP memory_limit so you can see whether your setting is being constrained.
To increase the server-level limit, edit php.ini, use .htaccess (if the host allows it), or contact your hosting provider.
The upload limit determines the maximum file size WordPress accepts for media uploads, plugin/theme zip files, and import operations.
Go to Debug Toolkit > Settings > PHP Settings > Upload Limit. WPDT applies the value through the upload_size_limit filter in WordPress.
The effective upload limit is the lowest of three values:
| Directive | Where it is set | What it controls |
|---|---|---|
upload_max_filesize | php.ini | Maximum size of a single uploaded file |
post_max_size | php.ini | Maximum size of the entire POST request body |
| WPDT upload limit | WordPress filter | WordPress-level cap applied by WPDT |
If upload_max_filesize is 2M in php.ini, setting a 50 MB limit in WPDT does not allow 50 MB uploads. PHP rejects the file before WordPress processes it. Both upload_max_filesize and post_max_size must be large enough to accommodate the desired upload size. post_max_size should be slightly larger than upload_max_filesize to account for form data sent alongside the file.
The Settings > PHP Settings page shows two columns for each setting:
wp-config.php specifiesThese can differ. If the configured memory limit is 512M but the server caps it at 256M, the effective value reads 256M. Check the effective column to confirm your settings are applied.
WPDT reads runtime values from ini_get() at page load. The values reflect the PHP configuration for the current request.
