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Function Reference/set post thumbnail size

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Set the default Featured Image (formerly Post Thumbnail) dimensions. To register additional image sizes for Featured Images use: add_image_size().

Note: To enable featured images, the current theme must include add_theme_support( 'post-thumbnails' ); in its functions.php file. See also Post Thumbnails.


 <?php set_post_thumbnail_size$width$height$crop ); ?> 


(int) (optional) The post thumbnail width in pixels.
Default: 0
(int) (optional) The post thumbnail height in pixels.
Default: 0
(boolean) (optional) Crop the image or not. False - Soft proportional crop mode ; True - Hard crop mode.
Default: false


Default Usage

To be used in the current theme's functions.php file.

add_theme_support( 'post-thumbnails' );
set_post_thumbnail_size( 150, 150 );


This function will not resize your existing feature images. To set net size to existing images use regenerate thumbnail plugins

Crop Mode

Set the default Post Thumbnail size by resizing the image proportionally (that is, without distorting it):

set_post_thumbnail_size( 50, 50 ); // 50 pixels wide by 50 pixels tall, resize mode

Set the default Post Thumbnail size by cropping the image (either from the sides, or from the top and bottom):

set_post_thumbnail_size( 50, 50, true ); // 50 pixels wide by 50 pixels tall, crop mode

Change Log

Source File

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


Post Thumbnails:

See also index of Function Reference and index of Template Tags.