How to Easily Serve Scaled Images in WordPress (Step by Step)

Have you ever visited a site and left within seconds because the images wouldn't load fast enough? That's exactly what your visitors might be experiencing if you're not serving scaled images on your WordPress site. 

This problem happens when your images are too large for their display size, which causes your site to load slowly and negatively impacts the user experience.

But don't worry, we've got you covered! Follow the quick tutorial below to learn how to serve scaled images easily!

Why Must You Serve Scaled Images?

Scaled images are images that have been resized to match the exact dimensions at which they will be displayed on a webpage. This is different from original uploads, which usually have much larger sizes and resolutions.

For example, your original featured image may be 4000 x 3000 pixels, but your website only displays it at 800 x 600 pixels. If the original image is used instead of the scaled-down version, your site will load more slowly.

When images are not properly scaled, the browser has to resize them manually on the fly. This will slow down page load, forcing users to wait and potentially increase the bounce rate.

It's important to use scaled images because not doing so can lead to several issues:

• Unnecessary loading times, as users have to download larger files than needed.
• Pixelated or blurry images, if the image is too small and gets stretched.
• Increased processing time, as the browser has to resize images on the fly, causing delays in displaying content.

Step-by-Step Guide

1. Use Image Editing Tools

This method offers faster image resizing by using editing tools. You can use tools like Adobe Photoshop to create properly scaled images. Photoshop allows extensive customization so you can decide pixel dimensions based on the size requirements.

If you're looking for a free alternative, online tools like PhotoPea are a good option. But. for this tutorial, we'll focus on Photoshop because of its comprehensive features.

To resize an image before uploading, follow the tutorial below:

• Open your image in Photoshop.
• Click the Image tab and select Image Size.

• In the dialog box that appears, change the image size according to the webpage's display requirements. 

For example, if your original image is 1281 x 493 px and you want to scale it to 3600 x 2400 px, enter the new dimensions. 

• Change the Resolution to 72 PPI for web use, or 300 PPI if you need high print quality.
• Then, select a resampling method. The two most suitable options for web optimization are:

• Click OK to apply the changes. Your image is now resized.
• To save the image, open the File tab and select Export.

• Click Export As and choose any file format and adjust the settings to achieve the smallest possible file size without losing too much image quality. 

2. Leverage WordPress's Built-In Image Sizes

If you prefer not to install any third-party software, you can use the built-in image editor in WordPress. With this tool, you can perform basic image editing tasks such as cropping, flipping, and resizing.

You can access this feature by clicking on any image in your post or media library. Additionally, you can define custom image sizes by modifying the functions.php file in your theme.

To keep things simple, let's start with a basic guide below:

• Upload your image to your WordPress post. 

• Select the image, then click Replace and choose Open Media Library from the menu. 

• In the sidebar, click Edit Image.

• You'll be taken to the image editor. Click on Scale to resize an image 

• Enter the new dimension for your image. For example, change it from 1198 × 744 px to 805 x 500 px. The aspect ratio is constrained, so the other value will adjust automatically based on the width or height you enter. 

• Click the Scale button to apply the changes.
• Your image is now scaled and ready to use in your post.

3. Utilize Plugins

• Install and activate WP Meta SEO on your WordPress site.

• From your WordPress dashboard, go to WP Meta SEO > Image editor.

• Open the Image SEO & HTML Resize settings.

• Enable the Dynamic Image Resizing option to allow WP Meta SEO to automatically resize images based on their display size.

• Define the maximum width and height values to control how images are resized on the front end.

Once enabled, WP Meta SEO will automatically adjust image dimensions when they are displayed on your site, ensuring optimal image sizes without manual intervention. This approach improves page speed, enhances SEO performance, and provides a better user experience—especially for image-heavy websites. 

For more details, you can explore the official documentation and feature overview:

• WP Meta SEO Image SEO & HTML Resize feature
• Dynamic Image Resizing documentation

4. Implement responsive images using the srcset attribute

The srcset attribute is used in the <img> tag in HTML to provide different image sources for various screen resolutions. By adding this attribute, the browser can select the most appropriate image based on the user's device.

For example, if a user accesses your website on a mobile device with a low-resolution display, the browser will load a lower-resolution image to provide a smoother experience.

If you want to know how to serve scaled images manually, follow the instructions below:

• Open the website's HTML file through your code editor.
• Locate the <img> tag for the image you want to optimize.

• Edit the tag and add the srcset attribute, as shown in the picture. 

In this example, 100w and 400w indicate the actual width of each image. The browser will use this information to decide which image to load for the user's device.

• Save the changes and reload your website to see the result.

How to Identify Unscaled Images

After learning how to optimize images, it's also important to identify which images still need to be scaled and which ones are already optimized.

There are two common ways to check for any unscaled image, either by using tools or performing a regular site audit. Follow the tutorial below:

1. Using Google PageSpeed Insights

This is an essential tool that offers suggestions to help make your website faster. These suggestions are generated through in-depth analysis using Google Lighthouse. One common suggestion is to properly scale any image that is flagged as unscaled.

To do a quick check, you can follow the instruction below:

• Open Google PageSpeed Insight at https://pagespeed.web.dev.

• Paste the full URL of your webpage into the input field.
• Click Analyze to start the process.
• Wait for it to finish. PSI will then provide you a performance report.
• Scroll down to find an entry labeled Properly size images.
• If present, you will see a list of unscaled images found on your site.

If one of your images is flagged as unscaled, Google PageSpeed Insights may offer several suggestions, including:

• Serving images in next-gen formats, such as WebP, AVIF, JPEG XR, or JPEG2000.
• Resizing images properly to meet different size requirements, like resizing to 1000 x 1000 px for a product detail page, or 400 x 400 px for a product listing page.
• Using lazy loading, so only images visible on the user's screen are loaded right away.

2. Performing a Regular Site Audit

Conducting regular site audits provides you with deep insights into your site's health and performance.

When auditing, try to prioritize reviewing your site architecture and user experience to uncover any potential issues.

This process can also reveal image optimization opportunities. Be sure to test your site across different devices, such as mobile, tablet, and desktop, to ensure a consistent experience.

Also, pay attention to whether images are properly scaled. If they're not, don't forget to follow the tutorial above.

Conclusion

Using scaled images is essential for optimizing site performance, especially on mobile devices. It helps your pages load faster and reduces the bounce rate.

However, scaling a large number of images can be time-consuming. Consider using a plugin like WP Media Folder, which lets you automatically resize, organize, and replace images while ensuring they remain optimized for performance.