diff --git a/Changelog.yaml b/Changelog.yaml
index cd825750a0..e030b688df 100644
--- a/Changelog.yaml
+++ b/Changelog.yaml
@@ -5,7 +5,7 @@
 # Also, each release can have new and improved recipes.
 
 - version: 0.7.21
-  date: 2010-10-1
+  date: 2010-10-01
 
   new features:
     - title: "Automatic backup of the calibre metadata database"