diff --git a/CHANGES b/CHANGES
index 8d950c3f5..1c27ebb73 100644
--- a/CHANGES
+++ b/CHANGES
@@ -15,6 +15,7 @@ Bugfixes:
  - GBA Serialize: Savestates now properly store prefetch
  - PSP2: Fix accelerometer range
  - PSP2: Actually load screen mode setting
+ - Qt: Fix bug in software renderer scaling
 Misc:
  - 3DS: Use blip_add_delta_fast for a small speed improvement
  - OpenGL: Log shader compilation failure
diff --git a/src/platform/qt/DisplayQt.cpp b/src/platform/qt/DisplayQt.cpp
index a18782e85..68a68e578 100644
--- a/src/platform/qt/DisplayQt.cpp
+++ b/src/platform/qt/DisplayQt.cpp
@@ -62,7 +62,7 @@ void DisplayQt::paintEvent(QPaintEvent*) {
 	QSize ds = s;
 	if (isAspectRatioLocked()) {
 		if (s.width() * m_height > s.height() * m_width) {
-			ds.setWidth(s.height() * m_width / 2);
+			ds.setWidth(s.height() * m_width / m_height);
 		} else if (s.width() * m_height < s.height() * m_width) {
 			ds.setHeight(s.width() * m_height / m_width);
 		}