diff --git a/src/wayland/subcompositor_interface.cpp b/src/wayland/subcompositor_interface.cpp
index 2a57e1f962..877c4dec42 100644
--- a/src/wayland/subcompositor_interface.cpp
+++ b/src/wayland/subcompositor_interface.cpp
@@ -288,6 +288,24 @@ SubSurfaceInterface::Mode SubSurfaceInterface::mode() const
     return d->mode;
 }
 
+bool SubSurfaceInterface::isSynchronized() const
+{
+    Q_D();
+    if (d->mode == Mode::Synchronized) {
+        return true;
+    }
+    if (d->parent.isNull()) {
+        // that shouldn't happen, but let's assume false
+        return false;
+    }
+    if (!d->parent->subSurface().isNull()) {
+        // follow parent's mode
+        return d->parent->subSurface()->isSynchronized();
+    }
+    // parent is no subsurface, thus parent is in desync mode and this surface is in desync mode
+    return false;
+}
+
 SubSurfaceInterface::Private *SubSurfaceInterface::d_func() const
 {
     return reinterpret_cast<SubSurfaceInterface::Private*>(d.data());
diff --git a/src/wayland/subcompositor_interface.h b/src/wayland/subcompositor_interface.h
index d908948dc3..56470e251a 100644
--- a/src/wayland/subcompositor_interface.h
+++ b/src/wayland/subcompositor_interface.h
@@ -70,6 +70,18 @@ public:
     };
     Mode mode() const;
 
+    /**
+     * Whether this SubSurfaceInterface is in synchronized mode.
+     * A SubSurface is in synchronized mode if either @link mode is
+     * @c Mode::Synchronized or if the parent surface is in synchronized
+     * mode. If a SubSurfaceInterface is in synchronized mode all child
+     * SubSurfaceInterfaces are also in synchronized mode ignoring the actual mode.
+     * @returns Whether this SubSurfaceInterface is in synchronized mode.
+     * @see mode
+     * @since 5.7
+     **/
+    bool isSynchronized() const;
+
     QPointer<SurfaceInterface> surface();
     QPointer<SurfaceInterface> parentSurface();