When I published my WordPress 6.6 release guide, one of the things I highlighted was the bumping of the PHP version and dropping support for WordPress of PHP 7.0 and 7.1. I did get asked how to check for the version of WordPress you run. Thankfully there’s an easy way to find out the WordPress PHP version.
The big scary warning to update PHP
The first thing you will tend to see will be if you are on a very old version of PHP (definitely 5.6 branch, but potentially the 7.0 & 7.1 releases now). Upon logging in, you will see a warning letting you know you are on an old version of PHP and you should upgrade.
This is a critical issue and should be updated as a matter of urgency. Not only the PHP version is out of date, but probably WordPress is as well, as updating WordPress means it has no guarantee of working. Furthermore, updating plugins may be impossible, as often plugin developers set a minimum PHP version for their software, so you wouldn’t be able to update plugins.
Having three security holes in your site is not good, and should be updated as a matter of urgency, hence the large visible update.
The best way to find out the WordPress PHP Version for the rest of us
If you don’t see the warning in the dashboard, you’re on a version of PHP that WordPress supports. Whilst that means you can update WordPress, you may have a few issues upgrading plugins. It is less of a concern, but should be fixed if you’re on an unsafe version of PHP.
To see the PHP version, you can check the Site Health Screen. Located under Tools > Site Health, it tells you quite a lot on things you should fix on your site. Clicking “Info” brings up the a list of drop downs. Expanding “Server” tells you information on your server architecture. One such item is your PHP version. This will tell you the PHP version your site is running on.
Which version of PHP should you use for WordPress?
As this is a blog post, I am probably not best placed to specify a version of WordPress to recommend. The majority of the sites I manage are either on 8.1 or 8.2 at the time of writing (19th July 2024). However, that could change as this blog post ages. I’d recommend the following two places to check. The first is the minimum requirements of WordPress. This will tell you the minimum PHP version that WordPress is currently tested on. However, for security, you should also check the PHP Supported Versions page which shows the versions of PHP that are currently either being actively developed or having security updates applied to it. Pick a version that is currently being actively supported and potentially will be for a long time that WordPress runs on (sometimes the latest version of PHP is incompatible with WordPress), and you should be good to go.
Upgrading PHP
By and large – it’s not something you would normally do. Instead it’ll be your hosts’ responsibility to upgrade WordPress. Nevertheless, I recommend testing the site in the new version of WordPress to see what happens on a staging site. If you’re not sure how to do this, do please get in touch and I’ll be happy to do it on your behalf.