Is your WordPress site bloated with unnecessary image sizes, slowing down your performance and hogging precious server space?
WordPress automatically creates multiple default image sizes when you upload images. These default WordPress image sizes can quickly become a burden if you have a lot of media files on your server.
This guide will teach you how to remove default image sizes using code snippets in your functions.php file and convenient plugins.
What are WordPress’s Default Image Sizes?
WordPress automatically generates several sizes of each image you upload to your media library by default. This allows the WordPress engine to use a custom image with appropriate image quality to cater to various display scenarios across your website. Different use cases often have vastly different image quality requirements. For example, you can get away with serving users low-quality thumbnail images on mobile devices, but if you are displaying a photo album on a large screen, then you would most likely want to use a higher-resolution image.
WordPress automatically creates default size formats for different scenarios, which act as pre-defined variations of the original image. This approach allows WordPress to serve the most appropriate version based on the context, such as thumbnails, featured images, or larger displays within the content.
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While this system is designed to be helpful, it can sometimes create unnecessary image files, especially if your theme or website design doesn’t use all of these default sizes. This problem is exacerbated if you have a great many images on your website.
List of Default Image Sizes in WordPress:
In your WordPress dashboard, navigate to “Settings” > “Media” to view the current media settings configured on your WordPress website.
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- Thumbnail: Typically, a square image (default is 150×150 pixels) is intended for use in galleries, widgets, and other small display areas.
- Medium: A mid-sized image (default maximum width and height are 300 pixels) is used in content areas where a larger thumbnail is needed.
- Large: A larger image size (default maximum width and height are 1024 pixels) is suitable for displaying images within articles or pages requiring more detail.
- Full Size: The dimensions of the original uploaded image. This is not technically a “default size” in the same sense as the others, as WordPress doesn’t resize the original upload, but it’s always available.
In addition to the above-mentioned image sizes, themes and plugins can register their own custom image sizes, which can further increase the number of images generated when uploading.
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In the above screenshot, we can see multiple copies of the same image stored in the wp-content folder, each with a different resolution.
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Why Remove Default Image Sizes?
While the automatic creation of multiple image sizes is helpful for most people, there are several compelling reasons to remove or disable some of the default sizes in WordPress.
The primary reasons are to reduce server storage consumption and improve website performance. Each image uploaded results in multiple saved versions, which can quickly fill up valuable disk space, especially for sites with an extensive media library or frequent image uploads. This excessive storage usage can impact server performance and increase hosting costs, especially with providers that charge based on storage usage.
Additionally, generating unnecessary image sizes can negatively affect website loading times. Even though WordPress only serves the appropriate-sized image, the server still has to process and create all the various sizes during the upload process, which can consume valuable server resources. Less efficient hosting setups exacerbate this slowdown.
Moreover, if your theme or design doesn’t use all of these default sizes, you’re essentially creating files that are never used, adding unnecessary weight to your website and potentially impacting user experience.
By removing unused default image sizes, you can conserve storage space, improve website speed, and enhance overall performance, directly leading to a better experience for visitors and website administrators.
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How to Remove Default Image Sizes in WordPress
There are primarily two methods for removing default image sizes in WordPress: using plugin settings (if available) or code snippets within your theme’s functions.php file. The code snippet method offers more granular control but requires a basic understanding of PHP and should be approached with caution.
From WP Admin Settings (Plugin Method)
The simplest way to remove default image sizes is through a plugin. Many plugins offer this functionality directly within their settings panel; if you’re unsure which plugin to pick, we recommend reading a deep dive into image optimization plugins written by security experts at Patchstack.
We will use the EWWW Image Optimizer for this tutorial to show you how to do this. Follow the instructions below to change the default image generation behavior of WordPress:
- Install and Activate the Plugin: Search for the “EWWW Image Optimizer” plugin and install it through your WordPress admin dashboard.
- Access Plugin Settings: In the WordPress admin panel, navigate to the plugin’s settings page and select “Save storage space” during initial installation.
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- Configure Plugin: On the next screen, you will be asked to configure the basic settings for this plugin. Leave these settings to their default value and click “Save Settings”.
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- Disable Unwanted Sizes: After configuring the plugin, navigate to the “Resize” tab in the plugin’s interface. On this screen, simply uncheck the boxes next to the sizes you wish to disable.
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- Save Changes: Save the changes to apply the new settings. From this point forward, WordPress will no longer generate the disabled image sizes upon uploading new images.
Using Code Snippets (functions.php Method)
This method involves adding code directly to your theme’s functions.php
file.
We strongly recommend using a child theme to prevent these changes from being overwritten during theme updates. Also, incorrect code can break your site, so proceed cautiously and always back up your functions.php file.
- Access your functions.php file: Access this file through your WordPress admin panel by going to Appearance > Theme File Editor. Alternatively, you can access the file directly using an FTP client or “File Manager” from your RunCloud dashboard.
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- Add code to remove image sizes: To remove specific default image sizes, add the following code snippets to your functions.php file:
function remove_default_image_sizes( $sizes ) {
unset( $sizes['thumbnail'] ); // Remove thumbnail size
unset( $sizes['medium'] ); // Remove medium size
unset( $sizes['large'] ); // Remove large size
return $sizes;
}
add_filter( 'intermediate_image_sizes_advanced', 'remove_default_image_sizes' );
- Save the functions.php file: After adding the code, save the changes to your functions.php file. This will prevent WordPress from generating the specified image sizes for future uploads. In the following screenshot, we can see that WordPress only created one copy of the image (as we configured) – no additional copies of the image were created.
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Best Practices After Removing Default Image Sizes
After removing default image sizes, following these best practices is recommended to ensure your website displays correctly and remains optimized.
- Regenerating Thumbnails: Removing default image sizes only affects future image uploads. Existing images will still have the previously generated sizes. You must regenerate thumbnails to clean up your media library and reclaim storage space.
- Checking for Broken Images: After removing image sizes and regenerating thumbnails, it’s recommended to thoroughly check your website for broken images.
- Manually Review Pages: Visit your website’s pages and posts, paying close attention to areas where images are displayed, such as galleries, featured images, and within content.
- Use a Broken Link Checker: Consider using a broken link checker plugin or online tool to scan your website for broken image links. These tools can identify images that are no longer accessible due to the removal of their corresponding sizes.
- Address Broken Images: If you find broken images, replace them with correctly sized versions or adjust your theme’s code to use the appropriate image sizes. WordPress may automatically try to use a similar image size in some cases, so you may not notice broken images unless the appropriate sizes have been completely removed.
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Final Thoughts
Optimizing your WordPress image handling is a powerful way to improve your website’s performance and user experience. Understanding the default image sizes can significantly reduce server load, conserve storage space, and deliver a faster, more responsive website to your visitors.
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We offer a powerful, intuitive platform to simplify WordPress hosting and unlock peak performance. Forget about complex server configurations and technical headaches. RunCloud empowers you with easy-to-use tools to deploy, manage, and scale your WordPress sites on the cloud infrastructure of your choice.
We handle the server-side optimizations so you can focus on what matters most: creating amazing content and growing your audience.
With RunCloud, you get:
- Blazing-Fast Performance: Optimized server stacks, built-in caching, and easy Cloudflare integration.
- Simplified Server Management: Our intuitive control panel allows you to easily manage your servers and WordPress sites.
- Automatic Backups: Rest easy, knowing your website is safe and secure with automated backups.
- Enhanced Security: Robust security features protect your website from threats, including firewalls and malware scanning.
FAQs on Removing WordPress Default Image Sizes
Why should I remove default image sizes?
WordPress generates multiple image sizes by default, bloating your server space and slowing down your website. Removing unused sizes streamlines your media library, leading to faster loading times.
Will removing default sizes affect my existing images?
Removing default image sizes only prevents future uploads from generating those specific sizes. Your already uploaded images will remain untouched.
How can I restore default image sizes if needed?
You can restore default image sizes by re-enabling the corresponding code in your functions.php file (if you used that method) or deactivating/reactivating the plugin that removed them.
What plugins can help with image size management?
Several plugins, like “ThumbPress” or “Disable Generate Thumbnails”, offer user-friendly interfaces for managing and disabling default WordPress image sizes.
Is it safe to modify the functions.php file?
Modifying the functions.php file is generally safe if done correctly and carefully. Always back up your functions.php file or use a child theme before making changes. Incorrect code can break your site, so proceed with caution.
How do I know which image sizes to keep?
Analyze your theme’s code and website’s layout to identify which image sizes are used in your design. Only keep the image sizes actively displayed on your pages; this will ensure the best performance when delivering images to users.
What is the impact on SEO when removing image sizes?
Removing unnecessary image sizes can positively impact SEO by improving your website’s page speed, a key ranking factor for search engines. Faster loading times enhance user experience and reduce bounce rates, potentially boosting your search engine rankings.