diff --git a/AuthDialog.cpp b/AuthDialog.cpp
--- a/AuthDialog.cpp
+++ b/AuthDialog.cpp
@@ -105,30 +105,34 @@
         m_message = message;
     }
 
+    const qreal dpr = devicePixelRatioF();
+
     // loads the standard key icon
     QPixmap icon = KIconLoader::global()->loadIcon("dialog-password",
                                                    KIconLoader::NoGroup,
-                                                   KIconLoader::SizeHuge,
+                                                   KIconLoader::SizeHuge * dpr,
                                                    KIconLoader::DefaultState);
+    icon.setDevicePixelRatio(dpr);
     // create a painter to paint the action icon over the key icon
     QPainter painter(&icon);
     const int iconSize = icon.size().width();
     // the emblem icon to size 32
     int overlaySize = 32;
     // try to load the action icon
-    const QPixmap pixmap = KIconLoader::global()->loadIcon(iconName,
+    QPixmap pixmap = KIconLoader::global()->loadIcon(iconName,
                                                            KIconLoader::NoGroup,
-                                                           overlaySize,
+                                                           overlaySize * dpr,
                                                            KIconLoader::DefaultState,
                                                            QStringList(),
                                                            nullptr,
                                                            true);
+    pixmap.setDevicePixelRatio(dpr);
     // if we're able to load the action icon paint it over the
     // key icon.
     if (!pixmap.isNull()) {
-        QPoint startPoint;
+        QPointF startPoint;
         // bottom right corner
-        startPoint = QPoint(iconSize - overlaySize - 2,
+        startPoint = QPointF(iconSize - overlaySize - 2,
                             iconSize - overlaySize - 2);
         painter.drawPixmap(startPoint, pixmap);
     }