diff --git a/Userland/Libraries/LibWeb/CMakeLists.txt b/Userland/Libraries/LibWeb/CMakeLists.txt
index 390be0a0257..94ac688b035 100644
--- a/Userland/Libraries/LibWeb/CMakeLists.txt
+++ b/Userland/Libraries/LibWeb/CMakeLists.txt
@@ -631,6 +631,7 @@ set(SOURCES
     SecureContexts/AbstractOperations.cpp
     SRI/SRI.cpp
     StorageAPI/NavigatorStorage.cpp
+    StorageAPI/StorageKey.cpp
     StorageAPI/StorageManager.cpp
     Streams/AbstractOperations.cpp
     Streams/ByteLengthQueuingStrategy.cpp
diff --git a/Userland/Libraries/LibWeb/StorageAPI/StorageKey.cpp b/Userland/Libraries/LibWeb/StorageAPI/StorageKey.cpp
new file mode 100644
index 00000000000..5682d05b817
--- /dev/null
+++ b/Userland/Libraries/LibWeb/StorageAPI/StorageKey.cpp
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2024, Andrew Kaster <andrew@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibWeb/DOMURL/DOMURL.h>
+#include <LibWeb/HTML/Scripting/Environments.h>
+#include <LibWeb/StorageAPI/StorageKey.h>
+
+namespace Web::StorageAPI {
+
+// https://storage.spec.whatwg.org/#obtain-a-storage-key
+Optional<StorageKey> obtain_a_storage_key(HTML::Environment const& environment)
+{
+    // 1. Let key be the result of running obtain a storage key for non-storage purposes with environment.
+    auto key = obtain_a_storage_key_for_non_storage_purposes(environment);
+
+    // 2. If key’s origin is an opaque origin, then return failure.
+    if (key.origin.is_opaque())
+        return {};
+
+    // FIXME: 3. If the user has disabled storage, then return failure.
+
+    // 4. Return key.
+    return key;
+}
+
+// https://storage.spec.whatwg.org/#obtain-a-storage-key-for-non-storage-purposes
+StorageKey obtain_a_storage_key_for_non_storage_purposes(HTML::Environment const& environment)
+{
+    // 1. Let origin be environment’s origin if environment is an environment settings object; otherwise environment’s creation URL’s origin.
+    if (is<HTML::EnvironmentSettingsObject>(environment)) {
+        auto const& settings = static_cast<HTML::EnvironmentSettingsObject const&>(environment);
+        // FIXME: EnvironmentSettingsObject::origin() should be const :|
+        auto& mutable_settings = const_cast<HTML::EnvironmentSettingsObject&>(settings);
+        return { mutable_settings.origin() };
+    }
+    return { DOMURL::url_origin(environment.creation_url) };
+}
+
+}
diff --git a/Userland/Libraries/LibWeb/StorageAPI/StorageKey.h b/Userland/Libraries/LibWeb/StorageAPI/StorageKey.h
new file mode 100644
index 00000000000..e8a4051500a
--- /dev/null
+++ b/Userland/Libraries/LibWeb/StorageAPI/StorageKey.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2024, Andrew Kaster <andrew@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Optional.h>
+#include <LibWeb/Forward.h>
+#include <LibWeb/HTML/Origin.h>
+
+namespace Web::StorageAPI {
+
+// https://storage.spec.whatwg.org/#storage-keys
+struct StorageKey {
+
+    // A storage key is a tuple consisting of an origin (an origin). [HTML]
+    // NOTE: This is expected to change; see Client-Side Storage Partitioning https://privacycg.github.io/storage-partitioning/.
+    HTML::Origin origin;
+
+    friend bool operator==(StorageKey const& a, StorageKey const& b)
+    {
+        // To determine whether a storage key A equals storage key B, run these steps:
+        // 1. If A’s origin is not same origin with B’s origin, then return false.
+        // 2. Return true.
+        return a.origin.is_same_origin(b.origin);
+    }
+};
+
+Optional<StorageKey> obtain_a_storage_key(HTML::Environment const&);
+StorageKey obtain_a_storage_key_for_non_storage_purposes(HTML::Environment const&);
+
+}