diff --git a/src/MimeTypeGuesser.php b/src/MimeTypeGuesser.php
index 2be6d0a..17d292a 100644
--- a/src/MimeTypeGuesser.php
+++ b/src/MimeTypeGuesser.php
@@ -598,6 +598,7 @@ class MimeTypeGuesser
         'audio/adpcm' => 'adp',
         'audio/basic' => 'au',
         'audio/midi' => 'mid',
+        'audio/mp3' => 'mp3',
         'audio/mp4' => 'mp4a',
         'audio/mpeg' => 'mpga',
         'audio/ogg' => 'oga',