diff --git a/libkcardgame/kabstractcarddeck.cpp b/libkcardgame/kabstractcarddeck.cpp
--- a/libkcardgame/kabstractcarddeck.cpp
+++ b/libkcardgame/kabstractcarddeck.cpp
@@ -75,19 +75,20 @@
         d->renderer();
     }
 
+    const auto size = m_size * qApp->devicePixelRatio();
     foreach ( const QString & element, m_elementsToRender )
     {
         {
             QMutexLocker l( &m_haltMutex );
             if ( m_haltFlag )
                 return;
         }
 
-        QString key = keyForPixmap( element, m_size );
+        QString key = keyForPixmap( element, size );
         if ( !d->cache->contains( key ) )
         {
             //qCDebug(LIBKCARDGAME_LOG) << "Renderering" << key << "in rendering thread.";
-            QImage img = d->renderCard( element, m_size );
+            QImage img = d->renderCard( element, size );
             d->cache->insertImage( key, img );
             emit renderingDone( element, img );
         }
@@ -197,24 +198,27 @@
         return QPixmap();
 
     QPixmap & stored = it.value().cardPixmap;
-    if ( stored.size() != currentCardSize )
+    const auto dpr = qApp->devicePixelRatio();
+    QSize requestedCardSize = currentCardSize * dpr;
+    if ( stored.size() != requestedCardSize )
     {
-        QString key = keyForPixmap( elementId , currentCardSize );
+        QString key = keyForPixmap( elementId , requestedCardSize );
         if ( !cache->findPixmap( key, &stored ) )
         {
             if ( stored.isNull() )
             {
                 //qCDebug(LIBKCARDGAME_LOG) << "Renderering" << key << "in main thread.";
-                QImage img = renderCard( elementId, currentCardSize );
+                QImage img = renderCard( elementId, requestedCardSize );
                 cache->insertImage( key, img );
                 stored = QPixmap::fromImage( img );
             }
             else
             {
-                stored = stored.scaled( currentCardSize );
+                stored = stored.scaled( requestedCardSize );
             }
         }
-        Q_ASSERT( stored.size() == currentCardSize );
+        Q_ASSERT( stored.size() == requestedCardSize );
+        stored.setDevicePixelRatio( dpr );
     }
     return stored;
 }
@@ -235,16 +239,19 @@
 
     // If the currentCardSize has changed since the rendering was performed,
     // we sadly just have to throw it away.
-    if ( image.size() != currentCardSize )
+    const auto dpr = qApp->devicePixelRatio();
+    if ( image.size() != currentCardSize * dpr)
         return;
 
     // The RenderingThread just put the image in the cache, but due to the
     // volatility of the cache there's no guarantee that it'll still be there
     // by the time this slot is called, in which case we convert the QImage
     // passed in the signal.
-    if ( !cache->findPixmap( keyForPixmap( elementId, currentCardSize ), &pix ) )
+    if ( !cache->findPixmap( keyForPixmap( elementId, currentCardSize * dpr ), &pix ) )
         pix = QPixmap::fromImage( image );
 
+    pix.setDevicePixelRatio( dpr );
+
     QHash<QString,CardElementData>::iterator it;
     it = frontIndex.find( elementId );
     if ( it != frontIndex.end() )
diff --git a/libkcardgame/kcard.cpp b/libkcardgame/kcard.cpp
--- a/libkcardgame/kcard.cpp
+++ b/libkcardgame/kcard.cpp
@@ -312,7 +312,7 @@
     Q_UNUSED( option );
     Q_UNUSED( widget );
 
-    if ( pixmap().size() != d->deck->cardSize() )
+    if ( pixmap().size() != d->deck->cardSize() * pixmap().devicePixelRatio() )
     {
         QPixmap newPix = d->deck->cardPixmap( d->id, d->faceUp );
         if ( d->faceUp )
diff --git a/libkcardgame/kcardthemewidget.cpp b/libkcardgame/kcardthemewidget.cpp
--- a/libkcardgame/kcardthemewidget.cpp
+++ b/libkcardgame/kcardthemewidget.cpp
@@ -81,7 +81,8 @@
                 return;
         }
 
-        QImage img( d->previewSize, QImage::Format_ARGB32 );
+        const auto dpr = qApp->devicePixelRatio();
+        QImage img( d->previewSize * dpr, QImage::Format_ARGB32 );
         img.fill( Qt::transparent );
         QPainter p( &img );
 
@@ -100,7 +101,7 @@
         {
             foreach ( const QString & card, pile )
             {
-                renderer.render( &p, card, QRectF( QPointF( xPos, yPos ), size ) );
+                renderer.render( &p, card, QRectF( QPointF( xPos, yPos ) * dpr, size * dpr ) );
                 xPos += 0.3 * spacingWidth;
             }
             xPos += 1 * size.width() + ( 0.1 - 0.3 ) * spacingWidth;
@@ -147,6 +148,7 @@
     m_previews.clear();
 
     QList<KCardTheme> previewsNeeded;
+    const auto dpr = qApp->devicePixelRatio();
 
     foreach( const KCardTheme & theme, KCardTheme::findAllWithFeatures( d->requiredFeatures ) )
     {
@@ -157,8 +159,10 @@
         QDateTime timestamp;
         if ( cacheFind( d->cache, timestampKey( theme ), &timestamp )
              && timestamp >= theme.lastModified() 
-             && d->cache->findPixmap( previewKey( theme, d->previewString ), pix ) )
+             && d->cache->findPixmap( previewKey( theme, d->previewString ), pix )
+             && pix->size() == d->previewSize * dpr )
         {
+            pix->setDevicePixelRatio( dpr );
             m_previews.insert( theme.displayName(), pix );
         }
         else
@@ -199,6 +203,7 @@
     cacheInsert( d->cache, timestampKey( theme ), theme.lastModified() );
 
     QPixmap * pix = new QPixmap( QPixmap::fromImage( image ) );
+    pix->setDevicePixelRatio( qApp->devicePixelRatio() );
     delete m_previews.value( theme.displayName(), 0 );
     m_previews.insert( theme.displayName(), pix );
 
diff --git a/main.cpp b/main.cpp
--- a/main.cpp
+++ b/main.cpp
@@ -101,6 +101,8 @@
 
 int main( int argc, char **argv )
 {
+    QCoreApplication::setAttribute(Qt::AA_UseHighDpiPixmaps);
+
     QApplication app(argc, argv);
 
     KLocalizedString::setApplicationDomain("kpat");