diff --git a/README.md b/README.md
index d8a8d285cb..76bf4029e7 100644
--- a/README.md
+++ b/README.md
@@ -13,7 +13,7 @@ for manipulating **JavaScript dates** in **a browser** & **Node.js**.
 ```js
 import {format, compareAsc} from 'date-fns/esm'
 
-format(new Date(2014, 1, 11), 'MM/DD/YYYY')
+format(new Date(2014, 1, 11), 'MM/dd/yyyy')
 //=> '02/11/2014'
 
 const dates = [new Date(1995, 6, 2), new Date(1987, 1, 11), new Date(1989, 6, 10)]