How to delete a WordPress theme

If an old WordPress theme has had its day or you are revamping the look of your WordPress site, it’s a good idea to uninstall inactive or outdated WordPress themes. Unused themes take up unnecessary space in the backend and may have a negative impact on website performance. If you want to know how to remove a WordPress theme, you have three options, via Dashboard, WP-CLI, or FTP.

In WordPress only one theme can be active at a time. Additional WordPress themes are stored in the backend, which means they are an unnecessary burden on your website. Themes are useful as they can make your website more recognisable, but make sure that you stay true to your own style. WordPress blog themes as well as themes for online shops and other business sites should therefore not be changed regularly. It’s not necessary to store extra themes in the backend, which is why you should remove any that are unused. This has a positive effect on performance because many inactive themes may affect loading speed and make the site harder to manage.

Here are some reasons to remove a WordPress theme:

• Performance and updates: Can an inactive theme affect the performance of your website? From an admin perspective, yes, because inactive, outdated themes do affect the loading speed of the admin dashboard, which is your backend. When WordPress checks for new updates, it goes through every inactive theme, which takes up unnecessary time. In addition, too much occupied space affects website loading times, which leads to lower search engine rankings.
• Security: Even inactive, old themes can be found in your source code, which can make it easier for hackers to attack. In addition, themes that you do not use should also be updated for security reasons, which is another thing that negatively affects the site’s performance.
• Storage space: Every theme takes up valuable storage space. Depending on your hosting package, you probably want to use every bit of storage space wisely so that the site runs efficiently, and costs don’t rise. Inactive themes can lead to avoidable additional costs.

There are several reasons why you should not delete a theme even though you might not be using it now. It depends on what kind of theme it is and if you will need it in the future. In the following three cases it is advisable not to remove a WordPress theme even if it is inactive:

If you use parent and child themes on your site, active child themes will be disabled as soon as you delete an inactive parent theme. Fortunately, WordPress shows which are child and which are parent themes. If you are not sure, check your themes with one of many free WordPress theme detectors such as Google Chrome WordPress Theme Detector and Plugin Detector.

If the WordPress site in question is included in a WP multisite network where you only have administrator rights for a site, themes cannot be deleted without seeking permission. The reason being that a theme is also active on other sites in the network. If a site is part of a multisite network, it will be indicated by the ‘My Sites’ icon on the administrator page. However, if you have network administrator privileges, you should not delete themes randomly without checking which themes are in active use on other sites. An overview of active themes on network pages can be found using the Multisite Enhancements Plugin.

If you want to test a theme first before you activate it, WordPress staging is a suitable option. Otherwise, a theme can also be installed and activated directly. Bear in mind that the current theme will be deactivated. The theme you deactivate for testing purposes should not be deleted if you still need it or if you work in an administrator team.

If you’re definitely sure you want to delete a theme, you should first take some important safety precautions to prevent problems from arising.

You can test whether removing a theme will cause problems for your site by using a staging site. Staging sites are depictions of live versions of a WordPress site. So you can first delete the theme to check if everything still runs smoothly and that missing WordPress theme elements do not cause any problems in the page display. If everything looks fine, you can also delete it permanently on your live site.

It’s always a good idea to create a backup before you delete files or software or perform an update. This way you always have an undamaged backup to hand. Even when deleting a theme, you should first create a WordPress backup, which you can then use if your site needs to be restored for any reason. Here WordPress backup plugins can be helpful.

Once you’ve determined that you no longer need a theme, it’s not a parent theme, and it’s also backed up, there are three deletion options available to you. We present you each option in detail.

Step 2: Click the theme you want to uninstall to see its details. Click the ‘Delete’ field at the bottom right. Confirm that you really want to delete the theme by clicking ‘OK’. The theme and its data will then be removed.

WP-CLI stands for ‘WordPress Command Line Interface’. The open-source tool can be installed for free to manage your WordPress installation as you wish via command line commands, to install and activate WordPress plugins, and to manage your site. To use this option, it helps if you’re already familiar with the tool because if you make split-second decisions and cause errors, files could end up being deleted unintentionally.

Step 1: Open the WP-CLI tool and get a list of all installed themes. To do this, use the command:

Step 2: To only see inactive themes displayed, use the command:

Step 3: Use the following command to delete the selected theme. Enter the name of the theme folder here, not the name of the theme itself:

If you use a File Transfer Protocol (FTP) client to transfer data from your computer to your WordPress host’s server, you can also use FTP to delete the theme.

Step 1: Open your FTP client and go to the wp-content/themes directory.

Step 2: In the directory you will find all currently installed themes listed. Unfortunately, it does not show you which theme is currently active. This is why it’s important to create a backup beforehand, especially in this case. Go to the theme you want to delete and right-click on it. The context menu will now open.

Step 3: Click on ‘Delete’ and confirm that you really want to delete the theme. The theme will then be removed.