diff --git a/scripts/install b/scripts/install
index 11a4b92..1d175b2 100644
--- a/scripts/install
+++ b/scripts/install
@@ -20,7 +20,7 @@ mail=$(ynh_user_get_info --username=$admin --key=mail)
 #=================================================
 ynh_script_progression --message="Validating installation parameters..."
 
-if [[ ${#admin} < 5 ]]; then
+if [[ $admin < 5 ]]; then
     ynh_die --message="Admin username minimum length is 5"
 fi