When you insert media with the media upload, it will generate images of several sizes according to the media settings. But sometimes I only need thumbnails. Other times I only need medium images. If each post has images that aren't being used, it waste space.

Is it possible to select custom image size to be generated when you open Insert Media?

  • PS: I mean, for one post, only generate thumbnail, NO medium; for next post, generate thumbnail and medium.
    – user32161
    Commented Jun 8, 2013 at 9:06

1 Answer 1


Scaled images are generated at the time they are uploaded, not when inserted.

You can choose the sizes that WordPress automatically generates for images that are uploaded in your Dashboard Settings under Settings > Media.

Once an image has been inserted using Add Media, you can click the image and then click the edit image icon that appears in the top left of the image. Go to the Advanced tab, and you can set a new size for the image just for that post.

A new image is not created for the individual post, but instead an <img /> element is inserted with the width and height specified.

  • Is it possible to add ON/OFF button on new media page to control functions.php of adding the script by add_image_size( 'medium', 210, 9999 );
    – user32161
    Commented Jun 9, 2013 at 23:59

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.