diff --git a/src/utils/utf8.php b/src/utils/utf8.php
--- a/src/utils/utf8.php
+++ b/src/utils/utf8.php
@@ -289,7 +289,7 @@
  */
 function phutil_utf8_strlen($string) {
   if (function_exists('utf8_decode')) {
-    return strlen(utf8_decode($string));
+    return strlen(mb_convert_encoding($string, 'ISO-8859-1'));
   }
   return count(phutil_utf8v($string));
 }