diff --git a/sections/staffpm/makedonor.php b/sections/staffpm/makedonor.php
index be8b3ac3..d616e0b1 100644
--- a/sections/staffpm/makedonor.php
+++ b/sections/staffpm/makedonor.php
@@ -3,7 +3,7 @@
 if (!check_perms('users_give_donor')) {
 	error(403);
 }
-if (!is_number($_POST['id']) || !is_number($_POST['donation_amount']) || empty($_POST['donation_currency'])) {
+if (!is_number($_POST['id']) || !is_numeric($_POST['donation_amount']) || empty($_POST['donation_currency'])) {
 	error(404);
 }