diff --git a/core/includes/form.inc b/core/includes/form.inc
index 84921ed..c6974c4 100644
--- a/core/includes/form.inc
+++ b/core/includes/form.inc
@@ -4034,12 +4034,20 @@ function form_validate_number(&$element, &$form_state) {
 /**
  * Form element validation handler for #type 'range'.
  *
- * Make sure range elements always have a value. Default to 0. #required is not
- * supported for range elements.
+ * Make sure range elements always have a value. Default to 0. The 'required'
+ * attribute is not allowed for range elements.
  */
 function form_validate_range(&$element, &$form_state) {
   if ($element['#value'] === '') {
-    form_set_value($element, 0.0, $form_state);
+    $default_value = ($element['#min'] + $element['#max']) / 2;
+
+    // Round the default value to the step.
+    if (strtolower($element['#step']) != 'any') {
+      $steps = round($default_value / $element['#step']);
+      $default_value = $element['#step'] * $steps;
+    }
+
+    form_set_value($element, $default_value, $form_state);
   }
 }