diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index 072231d4054..43cf6bce3ce 100644
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -195,6 +195,11 @@ impl HTMLFormElementMethods for HTMLFormElement {
         let window = window_from_node(self);
         HTMLFormControlsCollection::new(window.r(), self.upcast(), filter)
     }
+
+    // https://html.spec.whatwg.org/multipage/#dom-form-length
+    fn Length(&self) -> i32 {
+        self.Elements().Length() as i32
+    }
 }
 
 #[derive(Copy, Clone, HeapSizeOf, PartialEq)]
diff --git a/components/script/dom/webidls/HTMLFormElement.webidl b/components/script/dom/webidls/HTMLFormElement.webidl
index 4fde856a6a5..d97de7dd22d 100644
--- a/components/script/dom/webidls/HTMLFormElement.webidl
+++ b/components/script/dom/webidls/HTMLFormElement.webidl
@@ -17,7 +17,7 @@ interface HTMLFormElement : HTMLElement {
            attribute DOMString target;
 
   [SameObject] readonly attribute HTMLFormControlsCollection elements;
-  //readonly attribute long length;
+  readonly attribute long length;
   //getter Element (unsigned long index);
   //getter (RadioNodeList or Element) (DOMString name);
 
diff --git a/tests/wpt/metadata/html/dom/interfaces.html.ini b/tests/wpt/metadata/html/dom/interfaces.html.ini
index 30a17856204..0a4948517a1 100644
--- a/tests/wpt/metadata/html/dom/interfaces.html.ini
+++ b/tests/wpt/metadata/html/dom/interfaces.html.ini
@@ -4758,9 +4758,6 @@
   [HTMLFormElement interface: existence and properties of interface object]
     expected: FAIL
 
-  [HTMLFormElement interface: attribute length]
-    expected: FAIL
-
   [HTMLFormElement interface: operation checkValidity()]
     expected: FAIL
 
@@ -4770,9 +4767,6 @@
   [HTMLFormElement interface: operation requestAutocomplete()]
     expected: FAIL
 
-  [HTMLFormElement interface: document.createElement("form") must inherit property "length" with the proper type (10)]
-    expected: FAIL
-
   [HTMLFormElement interface: document.createElement("form") must inherit property "checkValidity" with the proper type (15)]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/html/semantics/forms/the-form-element/form-nameditem.html.ini b/tests/wpt/metadata/html/semantics/forms/the-form-element/form-nameditem.html.ini
index 9409afa1a8a..3afc5ac928d 100644
--- a/tests/wpt/metadata/html/semantics/forms/the-form-element/form-nameditem.html.ini
+++ b/tests/wpt/metadata/html/semantics/forms/the-form-element/form-nameditem.html.ini
@@ -15,12 +15,6 @@
   [Named elements should override builtins]
     expected: FAIL
 
-  [Named items outside the form should not be returned (no children)]
-    expected: FAIL
-
-  [Named items outside the form should not be returned (one child)]
-    expected: FAIL
-
   [The form attribute should be taken into account for named getters (single element)]
     expected: FAIL