diff --git a/src/edgeTTS/__init__.py b/src/edgeTTS/__init__.py
index a6ed241..31c66d7 100755
--- a/src/edgeTTS/__init__.py
+++ b/src/edgeTTS/__init__.py
@@ -122,7 +122,7 @@ class Communicate:
 
         if not customspeak:
             wsmax = 2 ** 16
-            overhead = len(self.mkssmlmsg("", voice, pitch, rate, volume, customspeak=False))
+            overhead = len(self.mkssmlmsg("", voice, pitch, rate, volume, customspeak=False).encode('utf-8'))
             msgs = _minimize(escape(removeIncompatibleControlChars(msg)), b" ", wsmax - overhead)
 
         async with websockets.connect(