gallery – size is thumbnail by default change it to medium [duplicate]

Add below in you functions.php file, add_filter(‘post_gallery’,’wpse56909_post_gallery’,10,2); function wpse56909_post_gallery($output, $attr) { // We’re trusting author input, so let’s at least make sure it looks like a valid orderby statement if ( isset( $attr[‘orderby’] ) ) { $attr[‘orderby’] = sanitize_sql_orderby( $attr[‘orderby’] ); if ( !$attr[‘orderby’] ) unset( $attr[‘orderby’] ); } extract(shortcode_atts(array( ‘order’ => ‘ASC’, ‘orderby’ => … Read more

Custom image sizes

Of course, I don’t know what articles you’ve read – however, I’m pretty much sure they are about WordPress’ functionality to automatically resize images after upload, as in actual pixel width and height. What you are talking about, is scaling (via CSS). So in short: these are two different pair of shoes.