diff --git a/CHANGES b/CHANGES
index 4ad150ddf..5d52ef752 100644
--- a/CHANGES
+++ b/CHANGES
@@ -113,6 +113,7 @@ Misc:
  - GBA BIOS: Stub out SoundBias
  - Qt: Gamepads can now have both buttons and analog axes mapped to the same key
  - Qt: Increase usability of key mapper
+ - Qt: Show checkmark for window sizes
 
 0.2.1: (2015-05-13)
 Bugfixes:
diff --git a/src/platform/qt/ShortcutController.h b/src/platform/qt/ShortcutController.h
index 5cc6f06a4..811a34f34 100644
--- a/src/platform/qt/ShortcutController.h
+++ b/src/platform/qt/ShortcutController.h
@@ -103,6 +103,8 @@ public:
 	                  const QKeySequence& shortcut, const QString& visibleName, const QString& name);
 	void addMenu(QMenu* menu, QMenu* parent = nullptr);
 
+	QAction* getAction(const QString& name);
+
 	QKeySequence shortcutAt(const QModelIndex& index) const;
 	bool isMenuAt(const QModelIndex& index) const;
 
diff --git a/src/platform/qt/Window.cpp b/src/platform/qt/Window.cpp
index f0c219c4b..94b007c25 100644
--- a/src/platform/qt/Window.cpp
+++ b/src/platform/qt/Window.cpp
@@ -427,11 +427,27 @@ void Window::keyReleaseEvent(QKeyEvent* event) {
 	event->accept();
 }
 
-void Window::resizeEvent(QResizeEvent*) {
+void Window::resizeEvent(QResizeEvent* event) {
 	if (!isFullScreen()) {
 		m_config->setOption("height", m_screenWidget->height());
 		m_config->setOption("width", m_screenWidget->width());
 	}
+
+	int factor = 0;
+	if (event->size().width() % VIDEO_HORIZONTAL_PIXELS == 0 && event->size().height() % VIDEO_VERTICAL_PIXELS == 0 &&
+	    event->size().width() / VIDEO_HORIZONTAL_PIXELS == event->size().height() / VIDEO_VERTICAL_PIXELS) {
+		factor = event->size().width() / VIDEO_HORIZONTAL_PIXELS;
+	}
+	for (QMap<int, QAction*>::iterator iter = m_frameSizes.begin(); iter != m_frameSizes.end(); ++iter) {
+		bool enableSignals = iter.value()->blockSignals(true);
+		if (iter.key() == factor) {
+			iter.value()->setChecked(true);
+		} else {
+			iter.value()->setChecked(false);
+		}
+		iter.value()->blockSignals(enableSignals);
+	}
+
 	m_config->setOption("fullscreen", isFullScreen());
 }
 
@@ -920,10 +936,12 @@ void Window::setupMenu(QMenuBar* menubar) {
 	m_shortcutController->addMenu(frameMenu, avMenu);
 	for (int i = 1; i <= 6; ++i) {
 		QAction* setSize = new QAction(tr("%1x").arg(QString::number(i)), avMenu);
+		setSize->setCheckable(true);
 		connect(setSize, &QAction::triggered, [this, i]() {
 			showNormal();
 			resizeFrame(VIDEO_HORIZONTAL_PIXELS * i, VIDEO_VERTICAL_PIXELS * i);
 		});
+		m_frameSizes[i] = setSize;
 		addControlledAction(frameMenu, setSize, QString("frame%1x").arg(QString::number(i)));
 	}
 	QKeySequence fullscreenKeys;
diff --git a/src/platform/qt/Window.h b/src/platform/qt/Window.h
index 0e0bfe6d4..16295f264 100644
--- a/src/platform/qt/Window.h
+++ b/src/platform/qt/Window.h
@@ -148,6 +148,7 @@ private:
 	GameController* m_controller;
 	Display* m_display;
 	QList<QAction*> m_gameActions;
+	QMap<int, QAction*> m_frameSizes;
 	LogController m_log;
 	LogView* m_logView;
 	LoadSaveState* m_stateWindow;