diff --git a/README.md b/README.md
index f9bfc6c..fc7097c 100644
--- a/README.md
+++ b/README.md
@@ -27,6 +27,7 @@ duration            | Toast.durations.SHORT    | Number   | The duration of the
 visible             | false                    | Bool     | The visibility of toast. (Only for Toast Component)
 position            | Toast.positions.BOTTOM   | Number   | The position of toast showing on screen (A negative number represents the distance from the bottom of screen. A positive number represents the distance form the top of screen. `0` will position the toast to the middle of screen.)
 animation           | true                     | Bool     | Should preform an animation on toast appearing or disappearing.
+opacity             | 0.8                      | Number   | For animte from 0 to apacity.
 shadow              | true                     | Bool     | Should drop shadow around Toast element.
 backgroundColor     | null                     | String   | The background color of the toast.
 shadowColor         | null                     | String   | The shadow color of the toast.