diff --git a/src/wp-includes/class-wp-customize-manager.php b/src/wp-includes/class-wp-customize-manager.php
index 1948e7a794..ff5ae3bc46 100644
--- a/src/wp-includes/class-wp-customize-manager.php
+++ b/src/wp-includes/class-wp-customize-manager.php
@@ -5936,7 +5936,7 @@ public function _validate_header_video( $validity, $value ) {
 		$video = get_attached_file( absint( $value ) );
 		if ( $video ) {
 			$size = filesize( $video );
-			if ( 8 < $size / pow( 1024, 2 ) ) { // Check whether the size is larger than 8MB.
+			if ( 8 < $size / (1024 ** 2)) { // Check whether the size is larger than 8MB.
 				$validity->add(
 					'size_too_large',
 					__( 'This video file is too large to use as a header video. Try a shorter video or optimize the compression settings and re-upload a file that is less than 8MB. Or, upload your video to YouTube and link it with the option below.' )
diff --git a/src/wp-includes/deprecated.php b/src/wp-includes/deprecated.php
index e0494d8faa..791b472b15 100644
--- a/src/wp-includes/deprecated.php
+++ b/src/wp-includes/deprecated.php
@@ -3346,7 +3346,7 @@ function wp_convert_bytes_to_hr( $bytes ) {
 	$units = array( 0 => 'B', 1 => 'KB', 2 => 'MB', 3 => 'GB', 4 => 'TB' );
 	$log   = log( $bytes, KB_IN_BYTES );
 	$power = (int) $log;
-	$size  = pow( KB_IN_BYTES, $log - $power );
+	$size  = KB_IN_BYTES ** ($log - $power);
 
 	if ( ! is_nan( $size ) && array_key_exists( $power, $units ) ) {
 		$unit = $units[ $power ];