To give your site visitors the best experience, it’s important for your site’s images to load quickly. This guide will show you how to optimize your images by decreasing the file size while retaining the image’s quality.
A WordPress site can have any number of themes, layouts, and other factors that determine the recommended image size. Therefore, there’s no one-size-fits-all approach we can recommend here.
A good rule of thumb is to upload images that are 1.5 to 2 times the width of your theme’s content area. If the content area is 600px, a 1200px-wide photo, served full size, should look crisp and high-quality while still having a relatively small file size.
Modern digital cameras and smartphones capture high-quality images with large file sizes. When displaying these images on a site, you can reduce the file size by 50% or more while maintaining quality for viewers.
You can check the file size and dimensions from the Media Library using these steps:
- In your site’s dashboard, navigate to Media → Library.
- Click the image thumbnail you want to see the file size and dimensions for.
- View the file size and dimensions in the sidebar on the right.
Take a look at the image on your site. Does it appear in high quality but load slowly? For example, if it’s 5000px wide, consider reducing it to 2500px wide. If it still looks good, try decreasing the image size further, to 2000px or 1800px wide, until you find the right balance between image quality and size.
The following sections in this guide will show you how to reduce the image size with different tools.
There are numerous methods you can use to resize images. In the following sections, we’ll cover tools available on your computer, online programs, and more advanced software.
If you’re on Windows, Microsoft Paint is a quick option that’s already installed on your computer. Open your image in Paint, find the “Resize” option in the toolbar, and resize the image by percentage. Then save the new, smaller version.
If you’re on a Mac, the Preview app is a quick option that’s already installed on your computer. Open your image with Preview, click Tools in the menu, and select “Adjust Size”.
If you’d rather not install anything, these free online tools let you resize images right in your browser:
With these services, you can upload your image, choose a new size, and export the new version. Please note that these services are not affiliated with WordPress.com.
If you use the Jetpack app to post to your site, you can configure how it optimizes images. By default, the “Optimize Images” option is turned on. You can set the “Max Image Upload Size” so the original file is resized automatically when you upload it.
In the Jetpack app for iPhone and the Jetpack app for Android, adjust the settings by following these steps:
- Log into the Jetpack app on your phone.
- Tap your profile icon in the bottom right.
- Tap “App Settings“.
You can toggle “Optimize Images” off (not recommended) or adjust the “Max Image Upload Size“. The default is 2000 x 2000px.
For more control — like adjusting image quality and compression settings — you can use GNU Image Manipulation Program (GIMP). It’s a free alternative to Photoshop available for Windows, Mac, and Linux.
GIMP is a good choice if you’re optimizing many images or want to fine-tune the balance between file size and quality.
To reduce the image size using GIMP:
- Open the image in GIMP.
- Click the Image option in the menu, then select “Scale Image“.
- In the image size, change the width value to your desired size, then click the Scale button to apply the change.
- Select the File option in the menu. Then select “Export As“.
- Name your file ending with a “.jpg” and click the Export button.
- In the dialog box that opens, change Quality to 60 (or your desired level).
- In the Advanced Options section, change subsampling to 4:2:0 (chroma quartered).
- Click the Export button.
Here’s a comparison of the results. Use the slider to view each image in full:
Other image editing software tools may have easy options to quickly size and compress a batch of photos:
There are also web-based services you can use:
Resizing reduces your image’s dimensions (for example, from 5000px to 1200px wide), which significantly reduces the file size and preserves your site’s storage space. The automatic optimization options below handle compression—reducing the file size further without changing the dimensions or visible quality. For the best results, do both: resize your images before uploading, then enable automatic optimization.
Select the appropriate tab below:
This section of the guide applies to sites with the WordPress.com Business and Commerce plan. If you have a Business plan, make sure to activate it. For free sites and sites on the Personal and Premium plans, upgrade your plan to access this feature.
You can take advantage of our built-in Jetpack Site Accelerator (CDN) to automatically speed up image load times.
Follow these steps to activate Jetpack Site Accelerator:
- Visit your site’s dashboard.
- Navigate to Jetpack → Settings.
- Click the tab labeled Performance.
- Scroll down to the section named “Performance & speed.”
If your images look slightly blurry on some devices, it may be because of high-resolution “Retina” displays. Here’s how WordPress.com handles this automatically—and what it means for image sizing.
Retina displays have a much higher pixel density than regular displays, which can cause images with a regular pixel density to appear fuzzy. To prevent this, if we detect a Retina display, we serve the image at double the size so it displays maximum sharpness. This only works if the image in your Media Library is larger than the size on your site.
Even at double the maximum display size on your site, an image file should still be significantly smaller than at the full resolution used by your camera. This way, you can optimize your images and have them look good on Retina displays.
