diff --git a/examples/js/libs/msgpack-js.js b/examples/js/libs/msgpack-js.js
index 393ec6e11a69d5ae76da8a9bf84443344b68767a..87ca17764805b9259c1b199cbb13e4b8f1a047d2 100644
--- a/examples/js/libs/msgpack-js.js
+++ b/examples/js/libs/msgpack-js.js
@@ -87,7 +87,7 @@ function utf8Read(view, offset, length) {
     // Two byte character
     if ((byte & 0xe0) === 0xc0) {
       string += String.fromCharCode(
-        ((byte & 0x0f) << 6) | 
+        ((byte & 0x1f) << 6) | 
         (view.getUint8(++i) & 0x3f)
       );
       continue;