PHP is a server-side scripting language, most often used in web development. The WordPress core and most WordPress plugins and themes are written in PHP. PHP updates usually include several security and performance related improvements. It is therefore recommended to change to the newest PHP version as soon as it's possible. Learn more on the WordPress Support site.
Seravo's plan include tested automatic updates for WordPress core, plugins and themes, but automatic PHP updates are not included in them. This is because these updates have a higher change of breaking functionality on the site due to combatibility issues, so it's best for the site's developer to perform the update by themselves.
How to Check and Change the PHP Version of My Site?
We always recommend that you take a backup of the site before updating the PHP version. This will allow the site to be restored to as recent a version as possible, in case something goes wrong during the update, and other changes made to the site during the same day are not lost.
Need Help?
If you need help restoring your site from a backup, you can contact Seravo's customer support at [email protected].
Additionally, ensure that your WordPress core, themes, and plugins are updated to their latest versions and test updates in a staging environment to avoid potential risks on the production site.
You can find the list of active and discontinued PHP versions used in our service here.
Changing the PHP version from WordPress Dashboard
By logging to the admin panel of your WordPress site and going to the Tools > Upkeep tab, you get to change the PHP version of your site to your liking. The same tool also shows the current PHP version used.
Changing the PHP version from Command Line
You can use the command wp-check-php-version to display the current PHP version in use. If you use an older PHP version, the command will return a warning that the version's security support has ended. With a recent PHP version in use, command output will look like this:
==> Check PHP backends:
Found PHP mode definition: php8.4 in '/data/wordpress/nginx/php.conf'
Using PHP mode php8.4
PHP version is defined in php.conf file, which can be found under /data/wordpress/nginx directory. There you can set the version to your liking by editing the version number in line set $mode php8.4; . After that you must restart the nginx by running wp-restart-nginx.
With the command below, you can choose to do all of the above at once:
wp-php-set-version 8.4
After the change, it's good to check the error logs of the site to make sure the change didn’t trigger any errors. If issues arise after the update, ensure all site components are updated and consider reverting to a previous PHP version temporarily.
How to Check if My Site is Compatible With the Newest PHP Version?
Site's plugins compatibility with the newest PHP can be checked with wp-php-compatibility-check, that’ll reveal PHP code incompatibilities and give you some details, why the plugin in question isn’t compatible. If the check returns errors, you can’t do a version update before the errors have been fixed.
Seravo’s plans do not include fixing a plugin/theme to work with the newest PHP version. Seravo only updates plugins and themes to the newest versions and it is generally on the plugin developers responsibility to maintain the plugin. If you can’t fix the errors yourself, you can contact our customer support for recommendations on digital agencies or freelancers who could offer you their help.
Common examples of errors include deprecated PHP functions or plugins not supporting the latest version (e.g., Call to undefined function create_function()). Updating or replacing problematic plugins/themes can resolve issues.
Checking PHP Combatibility from WordPress Dashboard
Compatibility checking is done from the same tab and section where you can change the PHP version, Tools > Upkeep.
Checking PHP Combatibility from Command Line
Run the command wp-php-compatibility-check via SSH. The test results are logged in the file /data/log/wp-php-compatibility.log and inside the log file you will find warnings, if there are any.
You can also use the wp-php-compatibility-check command to check the compatibility of an individual theme with the latest version of PHP:
wp-php-compatibility-check /data/wordpress/htdocs/wp-content/themes/twentytwentyfive/
The command can also be used to check the compatibility of a specific plugin:
wp-php-compatibility-check /data/wordpress/htdocs/wp-content/plugins/autodescription
Additionally, you can view compatibility for a specific version of PHP by adding the version number to the end of the command:
wp-php-compatibility-check /data/wordpress/htdocs/wp-content/themes/twentytwentyfive 8.5
Official PHP Version Migration Documentation
For site developers, we recommend checking the PHP's official documentation for each version upgrade: