diff --git a/powerdnsadmin/routes/index.py b/powerdnsadmin/routes/index.py
index cd93181..2c2dfbd 100644
--- a/powerdnsadmin/routes/index.py
+++ b/powerdnsadmin/routes/index.py
@@ -665,7 +665,7 @@ def register():
       email = request.form.get('email', '').strip()
       rpassword = request.form.get('rpassword', '')
 
-      is_valid_email = re.compile(r'[\w\.-]+@[\w\.-]+')
+      is_valid_email = re.compile(r'^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+$')
 
       error_messages = {}
       if not firstname: