diff --git a/Userland/Libraries/LibWeb/DOM/Document.cpp b/Userland/Libraries/LibWeb/DOM/Document.cpp
index aa5eeffebc..e6a64c3994 100644
--- a/Userland/Libraries/LibWeb/DOM/Document.cpp
+++ b/Userland/Libraries/LibWeb/DOM/Document.cpp
@@ -897,8 +897,23 @@ void Document::set_active_element(Element* element)
         m_layout_root->set_needs_display();
 }
 
-void Document::set_ready_state(const String& ready_state)
+String Document::ready_state() const
 {
+    switch (m_ready_state) {
+    case HTML::DocumentReadyState::Loading:
+        return "loading"sv;
+    case HTML::DocumentReadyState::Interactive:
+        return "interactive"sv;
+    case HTML::DocumentReadyState::Complete:
+        return "complete"sv;
+    }
+    VERIFY_NOT_REACHED();
+}
+
+void Document::set_ready_state(HTML::DocumentReadyState ready_state)
+{
+    if (m_ready_state == ready_state)
+        return;
     m_ready_state = ready_state;
     dispatch_event(Event::create(HTML::EventNames::readystatechange));
 }
diff --git a/Userland/Libraries/LibWeb/DOM/Document.h b/Userland/Libraries/LibWeb/DOM/Document.h
index 83977757d8..47682b87f9 100644
--- a/Userland/Libraries/LibWeb/DOM/Document.h
+++ b/Userland/Libraries/LibWeb/DOM/Document.h
@@ -26,6 +26,7 @@
 #include <LibWeb/DOM/ExceptionOr.h>
 #include <LibWeb/DOM/NonElementParentNode.h>
 #include <LibWeb/DOM/ParentNode.h>
+#include <LibWeb/HTML/DocumentReadyState.h>
 #include <LibWeb/HTML/HTMLScriptElement.h>
 #include <LibWeb/HTML/History.h>
 
@@ -226,8 +227,8 @@ public:
     const Document* associated_inert_template_document() const { return m_associated_inert_template_document; }
     void set_associated_inert_template_document(Document& document) { m_associated_inert_template_document = document; }
 
-    const String& ready_state() const { return m_ready_state; }
-    void set_ready_state(const String&);
+    String ready_state() const;
+    void set_ready_state(HTML::DocumentReadyState);
 
     void ref_from_node(Badge<Node>)
     {
@@ -358,7 +359,7 @@ private:
     bool m_created_for_appropriate_template_contents { false };
     RefPtr<Document> m_associated_inert_template_document;
 
-    String m_ready_state { "loading" };
+    HTML::DocumentReadyState m_ready_state { HTML::DocumentReadyState::Loading };
     String m_content_type { "application/xml" };
     Optional<String> m_encoding;
 
diff --git a/Userland/Libraries/LibWeb/HTML/DocumentReadyState.h b/Userland/Libraries/LibWeb/HTML/DocumentReadyState.h
new file mode 100644
index 0000000000..d487fec747
--- /dev/null
+++ b/Userland/Libraries/LibWeb/HTML/DocumentReadyState.h
@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+namespace Web::HTML {
+
+enum class DocumentReadyState {
+    Loading,
+    Interactive,
+    Complete,
+};
+
+}
diff --git a/Userland/Libraries/LibWeb/HTML/Parser/HTMLParser.cpp b/Userland/Libraries/LibWeb/HTML/Parser/HTMLParser.cpp
index 74508b327a..e3fb50a352 100644
--- a/Userland/Libraries/LibWeb/HTML/Parser/HTMLParser.cpp
+++ b/Userland/Libraries/LibWeb/HTML/Parser/HTMLParser.cpp
@@ -188,7 +188,7 @@ void HTMLParser::the_end()
     // FIXME: 2. Set the insertion point to undefined.
 
     // 3. Update the current document readiness to "interactive".
-    m_document->set_ready_state("interactive");
+    m_document->set_ready_state(HTML::DocumentReadyState::Interactive);
 
     // 4. Pop all the nodes off the stack of open elements.
     while (!m_stack_of_open_elements.is_empty())
@@ -240,7 +240,7 @@ void HTMLParser::the_end()
     // 9. Queue a global task on the DOM manipulation task source given the Document's relevant global object to run the following steps:
     queue_global_task(HTML::Task::Source::DOMManipulation, *m_document, [document = m_document]() mutable {
         // 1. Update the current document readiness to "complete".
-        document->set_ready_state("complete");
+        document->set_ready_state(HTML::DocumentReadyState::Complete);
 
         // 2. If the Document object's browsing context is null, then abort these steps.
         if (!document->browsing_context())