diff --git a/Libraries/LibWeb/IndexedDB/Internal/Algorithms.cpp b/Libraries/LibWeb/IndexedDB/Internal/Algorithms.cpp
index f018aab5c95..8b2d08fb963 100644
--- a/Libraries/LibWeb/IndexedDB/Internal/Algorithms.cpp
+++ b/Libraries/LibWeb/IndexedDB/Internal/Algorithms.cpp
@@ -589,4 +589,36 @@ JS::Value convert_a_key_to_a_value(JS::Realm& realm, GC::Ref<Key> key)
     VERIFY_NOT_REACHED();
 }
 
+// https://w3c.github.io/IndexedDB/#valid-key-path
+bool is_valid_key_path(KeyPath const& path)
+{
+    // A valid key path is one of:
+    return path.visit(
+        [](String const& value) -> bool {
+            // * An empty string.
+            if (value.is_empty())
+                return true;
+
+            // FIXME: * An identifier, which is a string matching the IdentifierName production from the ECMAScript Language Specification [ECMA-262].
+            return true;
+
+            // FIXME: * A string consisting of two or more identifiers separated by periods (U+002E FULL STOP).
+            return true;
+
+            return false;
+        },
+        [](Vector<String> const& values) -> bool {
+            // * A non-empty list containing only strings conforming to the above requirements.
+            if (values.is_empty())
+                return false;
+
+            for (auto const& value : values) {
+                if (!is_valid_key_path(value))
+                    return false;
+            }
+
+            return true;
+        });
+}
+
 }
diff --git a/Libraries/LibWeb/IndexedDB/Internal/Algorithms.h b/Libraries/LibWeb/IndexedDB/Internal/Algorithms.h
index 2814a282127..7bc329ffca6 100644
--- a/Libraries/LibWeb/IndexedDB/Internal/Algorithms.h
+++ b/Libraries/LibWeb/IndexedDB/Internal/Algorithms.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <AK/Variant.h>
 #include <LibJS/Runtime/Realm.h>
 #include <LibWeb/IndexedDB/IDBRequest.h>
 #include <LibWeb/IndexedDB/Internal/Key.h>
@@ -13,6 +14,8 @@
 
 namespace Web::IndexedDB {
 
+using KeyPath = Variant<String, Vector<String>>;
+
 WebIDL::ExceptionOr<GC::Ref<IDBDatabase>> open_a_database_connection(JS::Realm&, StorageAPI::StorageKey, String, Optional<u64>, GC::Ref<IDBRequest>);
 bool fire_a_version_change_event(JS::Realm&, FlyString const&, GC::Ref<DOM::EventTarget>, u64, Optional<u64>);
 ErrorOr<GC::Ref<Key>> convert_a_value_to_a_key(JS::Realm&, JS::Value, Vector<JS::Value> = {});
@@ -21,5 +24,6 @@ GC::Ref<IDBTransaction> upgrade_a_database(JS::Realm&, GC::Ref<IDBDatabase>, u64
 WebIDL::ExceptionOr<u64> delete_a_database(JS::Realm&, StorageAPI::StorageKey, String, GC::Ref<IDBRequest>);
 void abort_a_transaction(IDBTransaction&, GC::Ptr<WebIDL::DOMException>);
 JS::Value convert_a_key_to_a_value(JS::Realm&, GC::Ref<Key>);
+bool is_valid_key_path(KeyPath const&);
 
 }