Get the available image sizes

Signature

get_intermediate_image_sizes()

Return

(array) Returns a filtered array of image size strings

Source

function get_intermediate_image_sizes() {
	global $_wp_additional_image_sizes;
	$image_sizes = array('thumbnail', 'medium', 'large'); // Standard sizes
	if ( isset( $_wp_additional_image_sizes ) && count( $_wp_additional_image_sizes ) )
		$image_sizes = array_merge( $image_sizes, array_keys( $_wp_additional_image_sizes ) );

	/**
	 * Filter the list of intermediate image sizes.
	 *
	 * @since 2.5.0
	 *
	 * @param array $image_sizes An array of intermediate image sizes. Defaults
	 *                           are 'thumbnail', 'medium', 'large'.
	 */
	return apply_filters( 'intermediate_image_sizes', $image_sizes );
}
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