WordPress Featured Image Size: Choose and Change It
Choose a featured image size that fits your WordPress theme. Understand crop ratios, block controls, generated sizes and thumbnail regeneration.
Reviewed 27 September 2026.
There is no universal featured image size
The right dimensions depend on your theme’s display width, crop ratio and where the image appears. A landscape social preview is not automatically the correct crop for every article card or hero.
Inspect a representative post and archive page on desktop and mobile. Record their displayed shape and width, then prepare an image large enough without unnecessary file weight.
Separate source, generated size and display
| Setting | Effect |
|---|---|
| Uploaded original | Source available for derived files |
| Registered image size | A file WordPress can generate |
| Theme or block controls | Layout dimensions and visual cropping |
Changing display height does not necessarily create a smaller file. Changing a thumbnail rule does not necessarily change the size requested by your theme.
Change display in a block theme
- Back up and open the relevant template in the Site Editor.
- Select the Post Featured Image block using List View.
- Review available dimension, ratio and scaling controls.
- Preview posts with different image shapes.
- Save only intended template changes and check public archives.
A shared template affects every post using it. For one exception, use a dedicated template or a supported per-post setting. See the block documentation.
Change generated image sizes when needed
Classic themes may provide Customizer or theme controls. Developers can register sizes with add_image_size() and make templates request them. Keep changes in a child theme or suitable site plugin.
New rules usually apply to new uploads. Existing files may need regeneration with a maintained tool. Back up, check storage and test a sample before processing the library. Regeneration cannot recover detail missing from the original.
Check the final image and social preview
- Keep faces and important text away from crop edges.
- Write meaningful alt text for informative images.
- Inspect the downloaded file, not just its displayed size.
- Compress images using supported formats.
- Check SEO-plugin social previews separately.
Only want to remove the large image from the article layout? Use our guide to hiding a featured image instead of deleting its assignment.
