diff --git a/script/resize.sh b/script/resize.sh
new file mode 100644
index 0000000..6829cdc
--- /dev/null
+++ b/script/resize.sh
@@ -0,0 +1,14 @@
+#!/bin/bash
+
+# $1 がない場合は終了
+if [ -z $1 ]; then
+    echo "Usage: $0 <directory>"
+    exit 1
+fi
+cd $1
+find . -type f -name "*.webp" | while read INPUT; do
+    if [ $(identify -format "%w" "$INPUT") -le 810 ]; then
+        continue
+    fi
+    cwebp -resize 1920 0 "$INPUT" -o "$INPUT"
+done