diff --git a/README.md b/README.md
index fb1f7c0..1896592 100644
--- a/README.md
+++ b/README.md
@@ -23,5 +23,9 @@ $ python -m SimpleHTTPServer 8080
 Now you can ask anything in this forum:
 + [https://groups.google.com/forum/#!forum/c3js](https://groups.google.com/forum/#!forum/c3js)
 
+## Playground
+Please fork this fiddle:
++ [http://jsfiddle.net/masayuki0812/7kYJu/](http://jsfiddle.net/masayuki0812/7kYJu/)
+
 ## License
 MIT