diff --git a/fhem/CHANGED b/fhem/CHANGED
index ddc3d9887..f8b56286f 100644
--- a/fhem/CHANGED
+++ b/fhem/CHANGED
@@ -1,5 +1,6 @@
 # Add changes at the top of the list. Keep it in ASCII, and 80-char wide.
 # Do not insert empty lines here, update check depends on it.
+  - feature: 57_Calendar: enable gzipped ical files (forum #31845)
   - bugfix: 70_Jabber.pm: XMPP DNS SVR record query added
   - bugfix: 70_PIONEERAVR: fixed "missed to call readingsBeginUpdate first" 
   - feature: fhemweb.js rewrite based on jQuery, single-widget-implementation
diff --git a/fhem/FHEM/57_Calendar.pm b/fhem/FHEM/57_Calendar.pm
index be7dc638b..9b1e60654 100644
--- a/fhem/FHEM/57_Calendar.pm
+++ b/fhem/FHEM/57_Calendar.pm
@@ -942,6 +942,17 @@ sub Calendar_GetUpdate($$) {
   #main::Debug $ical->asString();
 
   my @entries= @{$ical->{entries}};
+  if($#entries<0) {
+    eval { require Compress::Zlib; };
+    if($@) {
+      Log3 $hash, 1, "Calendar " . $hash->{NAME} . ": Maybe gzip data, but cannot load Compress::Zlib";
+    }
+    else {
+      $ics = Compress::Zlib::memGunzip($ics);
+      $ical->parse(split("\n",$ics));
+      @entries= @{$ical->{entries}};
+    }
+  };
   if($#entries<0) {
     Log3 $hash, 1, "Calendar " . $hash->{NAME} . ": Not an ical file at URL";
     $hash->{STATE}= "Not an ical file at URL";