diff --git a/test/test_utils.py b/test/test_utils.py
index 82ae77ea25..3d5a6ea6ba 100644
--- a/test/test_utils.py
+++ b/test/test_utils.py
@@ -1953,6 +1953,8 @@ def test_get_compatible_ext(self):
             vcodecs=[None], acodecs=[None], vexts=['webm'], aexts=['m4a']), 'mkv')
         self.assertEqual(get_compatible_ext(
             vcodecs=[None], acodecs=[None], vexts=['webm'], aexts=['webm']), 'webm')
+        self.assertEqual(get_compatible_ext(
+            vcodecs=[None], acodecs=[None], vexts=['webm'], aexts=['weba']), 'webm')
 
         self.assertEqual(get_compatible_ext(
             vcodecs=['h264'], acodecs=['mp4a'], vexts=['mov'], aexts=['m4a']), 'mp4')
diff --git a/yt_dlp/utils.py b/yt_dlp/utils.py
index 64c83a77a2..ee5340cd26 100644
--- a/yt_dlp/utils.py
+++ b/yt_dlp/utils.py
@@ -3656,7 +3656,7 @@ def get_compatible_ext(*, vcodecs, acodecs, vexts, aexts, preferences=None):
 
     COMPATIBLE_EXTS = (
         {'mp3', 'mp4', 'm4a', 'm4p', 'm4b', 'm4r', 'm4v', 'ismv', 'isma', 'mov'},
-        {'webm'},
+        {'webm', 'weba'},
     )
     for ext in preferences or vexts:
         current_exts = {ext, *vexts, *aexts}
@@ -5962,7 +5962,7 @@ def items_(self):
     common_video=('avi', 'flv', 'mkv', 'mov', 'mp4', 'webm'),
     video=('3g2', '3gp', 'f4v', 'mk3d', 'divx', 'mpg', 'ogv', 'm4v', 'wmv'),
     common_audio=('aiff', 'alac', 'flac', 'm4a', 'mka', 'mp3', 'ogg', 'opus', 'wav'),
-    audio=('aac', 'ape', 'asf', 'f4a', 'f4b', 'm4b', 'm4p', 'm4r', 'oga', 'ogx', 'spx', 'vorbis', 'wma'),
+    audio=('aac', 'ape', 'asf', 'f4a', 'f4b', 'm4b', 'm4p', 'm4r', 'oga', 'ogx', 'spx', 'vorbis', 'wma', 'weba'),
     thumbnails=('jpg', 'png', 'webp'),
     storyboards=('mhtml', ),
     subtitles=('srt', 'vtt', 'ass', 'lrc'),
@@ -6094,9 +6094,9 @@ class FormatSorter:
         'vext': {'type': 'ordered', 'field': 'video_ext',
                  'order': ('mp4', 'mov', 'webm', 'flv', '', 'none'),
                  'order_free': ('webm', 'mp4', 'mov', 'flv', '', 'none')},
-        'aext': {'type': 'ordered', 'field': 'audio_ext',
-                 'order': ('m4a', 'aac', 'mp3', 'ogg', 'opus', 'webm', '', 'none'),
-                 'order_free': ('ogg', 'opus', 'webm', 'mp3', 'm4a', 'aac', '', 'none')},
+        'aext': {'type': 'ordered', 'regex': True, 'field': 'audio_ext',
+                 'order': ('m4a', 'aac', 'mp3', 'ogg', 'opus', 'web[am]', '', 'none'),
+                 'order_free': ('ogg', 'opus', 'web[am]', 'mp3', 'm4a', 'aac', '', 'none')},
         'hidden': {'visible': False, 'forced': True, 'type': 'extractor', 'max': -1000},
         'aud_or_vid': {'visible': False, 'forced': True, 'type': 'multiple',
                        'field': ('vcodec', 'acodec'),