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Function Reference/image downsize


Scale an image to fit a particular size (such as 'thumb' or 'medium').

The $max_/$min_width for the Reserved Names will always be what you defined under "admin UI" » "Settings" » "Media". For detail, please refer to image_constrain_size_for_editor().

The URL might be the original image, or it might be a resized version. This function won't create a new resized copy, it will just return an already resized one if it exists.


(integer) (required) The ID of the image.
Default: None
(string) (optional) Size of image. It can be thumbnail or medium .
Default: medium

Return Values

False on failure, array on success. Array with image url, width, height, and whether is intermediate size ($is_intermediate), in that order is returned on success is returned. $is_intermediate is true if $url is a resized image, false if it is the original.

Source File

image_downsize() is located in wp-includes/media.php.


Add a function to select medium attachment images

Maybe you already know wp_get_attachment_thumb_url();. Now I'm showing how to do the same thing to return the url for the medium sized attachment.

function wp_get_attachment_medium_url( $id )
    $medium_array = image_downsize( $id, 'medium' );
    $medium_path = $medium_array[0];

    return $medium_path;

$id is the ID of the attachment

This can be really useful for plugins like WP-Choose-Thumb. With this function you can get the medium sized previews.

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