WordPress supports WebP since version 5.8

Since the WordPress version 5.8 which was released a few days ago, there is the possibility to load WebP images into the backend. You save about 30% of data volume compared to the previously common JPG format.

As with JPGs, you can integrate a code snippet via functions.php which influences the compression of the webP images during upload:

// Quality Settings for WebP Images 
function filter_webp_quality( $quality, $mime_type ) {
  if ( 'image/webp' === $mime_type ) {
     return 75; // set 0 - 100
  return $quality;
add_filter( 'ja_editor_set_quality', 'filter_webp_quality', 10, 2 );