1 files changed, 1 insertions, 1 deletions

diff --git a/kasi-totp.el b/kasi-totp.el
index b0f9a5f..f22c30c 100644
--- a/kasi-totp.el
+++ b/kasi-totp.el
@@ -81,7 +81,7 @@ string."
 
 This is not a 100% faithful implementation of RFC 4648. The
 concept of encoding partial quanta is not implemented fully."
-  (unless (mod (length string) 8)
+  (unless (zerop (mod (length string) 8))
     (error "Padding is incorrect"))
   (setq string (upcase string))
   (let* ((trimmed-array (append (string-trim-right string "=+") nil))