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To log WordPress errors without showing them to visitors, add three settings to wp-config.php: enable WP_DEBUG and WP_DEBUG_LOG, and set WP_DEBUG_DISPLAY to false. Reproduce the problem, then inspect the resulting log. On a live site, keep error display off and protect the log; WordPress recommends using debug tools on local or staging sites rather than live sites.
Enable WordPress debug logging
Back up your site or make the change on a staging copy first. Open the WordPress installation’s wp-config.php and add the following lines before /* That's all, stop editing! Happy blogging. */:
define( 'WP_DEBUG', true );
define( 'WP_DEBUG_LOG', true );
define( 'WP_DEBUG_DISPLAY', false );With this configuration, WordPress writes PHP errors to wp-content/debug.log by default and does not print them into page output. WP_DEBUG_LOG and WP_DEBUG_DISPLAY only take effect when WP_DEBUG is enabled. See the WordPress Developer Resources debugging guide and Learn WordPress debugging-log tutorial.
Development or staging
Use debug mode on a local or staging installation when possible. The WordPress Developer Resources guide says: “It is not recommended to use WP_DEBUG or the other debug tools on live sites; they are meant for local testing and staging installs.”
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If you must investigate a production problem, keep WP_DEBUG_DISPLAY set to false so diagnostic messages do not appear to visitors. The default log is inside wp-content, which may be web-accessible depending on server configuration. Where possible, set WP_DEBUG_LOG to a valid custom file path outside the public web root. If you cannot do that, restrict access to the log and its file permissions. Error logs can contain sensitive details, so do not publish or share them publicly.
Reproduce the error and read the log
- Save the configuration change, then repeat the action that triggers the blank page, PHP error, or plugin/theme failure.
- Open the configured log file, usually
wp-content/debug.log, and inspect the newest entries related to the time of the failure. - Look at the error message, file path, and any stack context. A path pointing into a plugin or theme can help identify the component involved; a WordPress core path may indicate a core-level issue or an interaction. Treat the log as diagnostic evidence, not proof by itself.
- Do not share raw log contents publicly. Redact sensitive paths or other identifying details before sending relevant excerpts to a trusted host or developer.
The WordPress debug log records server-side PHP errors; it will not diagnose a browser-side JavaScript problem. For JavaScript failures, use the browser’s developer tools and inspect the console.
If the dashboard is inaccessible
A fatal PHP error can prevent you from reaching the WordPress dashboard. WordPress Recovery Mode may send an email to the site administrator with a special login link, allowing access to address the component identified as causing the fatal error. Check the administrator email account, including spam folders. The official WordPress troubleshooting FAQ also advises contacting your host if recovery is not available. If you have file access, temporarily renaming the suspected plugin’s directory can deactivate it; restore the directory name after the issue is resolved or you are ready to troubleshoot further.
When the log is missing or empty
- Confirm that
WP_DEBUGis set totrueand that the settings appear before the “That’s all, stop editing!” comment. - Check that the configured log path is valid and that the server can write to it.
- Reproduce the error again after enabling logging; an old log may not contain the current failure.
- Ask your host where the PHP or server error logs are kept. Their location depends on the hosting environment, so there is no universal path.
The WordPress debugging guide describes the debug constants and other debugging approaches. Hosting support may also help with fatal errors or finding server logs; WordPress’s hosting FAQ discusses hosting features and professional support.
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Other WordPress debugging settings
For developers investigating specific issues, SCRIPT_DEBUG loads development versions of WordPress core CSS and JavaScript assets, which is useful when modifying those files. SAVEQUERIES records database queries for inspection but carries a performance cost. Do not leave diagnostic settings enabled on a live site after the investigation. The official debugging guide also covers plugins, automated tests, and step debugging. Xdebug and Ray are optional third-party tools for more advanced PHP debugging; they are not required for the basic logging procedure.
Quick Recap
Turn debugging off after troubleshooting
- Once the underlying fault is fixed, return to
wp-config.phpand disable debug mode by settingWP_DEBUGtofalseor removing the temporary debug constants. - Remove the diagnostic log or secure and rotate it if it must be retained.
- Test the site again to confirm the fix and check that diagnostic messages are not visible on public pages.
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