diff --git a/add-domain.php b/add-domain.php
index 23cb06f..89a87b6 100644
--- a/add-domain.php
+++ b/add-domain.php
@@ -67,7 +67,7 @@ limitations under the License.
                         </div>
                         <div class="form-group">
                             <label for="zone-mail" class="control-label">Email</label>
-                            <input type="text" class="form-control" id="zone-mail" placeholder="Email" autocomplete="off" data-regex="^.+\@.+\.[^.]+$" tabindex="3">
+                            <input type="text" class="form-control" id="zone-mail" placeholder="Email" autocomplete="off" data-regex="^.+@[^.]+(\.[^.]+)*$" tabindex="3">
                         </div>
                         <button id="zone-button-add" class="btn btn-primary" tabindex="8">Add</button>
                     </div>
diff --git a/edit-master.php b/edit-master.php
index fa60e70..4107ee6 100644
--- a/edit-master.php
+++ b/edit-master.php
@@ -70,7 +70,7 @@ limitations under the License.
                             </div>
                             <div class="form-group">
                                 <label for="soa-mail" class="control-label">Email</label>
-                                <input type="text" class="form-control" id="soa-mail" placeholder="Email" autocomplete="off" data-regex="^.+\@.+\.[^.]+$" tabindex="2">
+                                <input type="text" class="form-control" id="soa-mail" placeholder="Email" autocomplete="off" data-regex="^.+@[^.]+(\.[^.]+)*$" tabindex="2">
                             </div>
                             <button disabled type="submit" class="btn btn-primary" tabindex="7">Save</button>
                         </div>