diff --git a/build/update-demo-dates b/build/update-demo-dates
new file mode 100755
index 0000000..1ed31a4
--- /dev/null
+++ b/build/update-demo-dates
@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+
+read -p "Enter new year (4 digits): " year
+read -p "Enter new month (2 digits): " month
+read -p "This will modify files in the demos folder, is that ok? (y/n): " yn
+
+if [[ $yn != "y" ]]
+then
+	exit
+fi
+
+find "`dirname $0`/../demos" -type f \( -name '*.html' -o -name '*.json' \) -print0 \
+| xargs -0 sed -i '' -e "s/[0-9][0-9][0-9][0-9]-[0-9][0-9]/$year-$month/g"
+
+echo "DONE"
\ No newline at end of file