diff --git a/README.md b/README.md
index b5b719c6..cb729d41 100644
--- a/README.md
+++ b/README.md
@@ -11,7 +11,7 @@
 
 <p align="center">
 <a href="https://asciinema.org/a/223115">
-<img src="./screenshot/preview.gif"/>
+<img src="./screenshot/preview.gif" width="280" height="477"/>
 </a>
 </p>