diff --git a/src/ol/renderer/canvas/VectorTileLayer.js b/src/ol/renderer/canvas/VectorTileLayer.js
index 80d88dfc0c..efb3763063 100644
--- a/src/ol/renderer/canvas/VectorTileLayer.js
+++ b/src/ol/renderer/canvas/VectorTileLayer.js
@@ -796,7 +796,9 @@ class CanvasVectorTileLayerRenderer extends CanvasTileLayerRenderer {
     const context = tile.getContext(layer);
 
     // Increase tile size when overzooming for low pixel ratio, to avoid blurry tiles
-    pixelRatio = Math.max(pixelRatio, renderPixelRatio / pixelRatio);
+    pixelRatio = Math.round(
+      Math.max(pixelRatio, renderPixelRatio / pixelRatio)
+    );
     const size = source.getTilePixelSize(z, pixelRatio, projection);
     context.canvas.width = size[0];
     context.canvas.height = size[1];