diff --git a/Lib/mimetypes.py b/Lib/mimetypes.py
index 83477864400..ba4ea8257b6 100644
--- a/Lib/mimetypes.py
+++ b/Lib/mimetypes.py
@@ -437,7 +437,7 @@ def _default_mime_types():
         '.jpe'    : 'image/jpeg',
         '.jpeg'   : 'image/jpeg',
         '.jpg'    : 'image/jpeg',
-        '.js'     : 'application/x-javascript',
+        '.js'     : 'application/javascript',
         '.ksh'    : 'text/plain',
         '.latex'  : 'application/x-latex',
         '.m1v'    : 'video/mpeg',
diff --git a/Misc/ACKS b/Misc/ACKS
index f13c7b05e08..d8ddd325358 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -436,6 +436,7 @@ Jens B. Jorgensen
 Sijin Joseph
 Andreas Jung
 Tattoo Mabonzo K.
+Bohuslav Kabrda
 Bob Kahn
 Kurt B. Kaiser
 Tamito Kajiyama
diff --git a/Misc/NEWS b/Misc/NEWS
index 34143bfe974..895f31f373d 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -95,6 +95,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #15199: Fix JavaScript's default MIME type to application/javascript.
+  Patch by Bohuslav Kabrda.
+
 - Issue #15477: In cmath and math modules, add workaround for platforms whose
   system-supplied log1p function doesn't respect signs of zeros.