diff --git a/Decoding JSON.md b/Decoding JSON.md
index 3df75ca..3db7162 100644
--- a/Decoding JSON.md	
+++ b/Decoding JSON.md	
@@ -126,7 +126,7 @@ If the actual value doesn't match the target type, a default value will be retur
 
 If you want to know if some value is present, call `containsKey()`:
 
-    if (root.contains("extra"))
+    if (root.containsKey("extra"))
     {
         // root["extra"] is valid
     }