diff --git a/src/ol/Map.js b/src/ol/Map.js
index aa40e43e13..6252cd2eed 100644
--- a/src/ol/Map.js
+++ b/src/ol/Map.js
@@ -408,11 +408,11 @@ ol.Map.prototype.moveByPx = function(dx, dy) {
 };
 
 ol.Map.prototype.zoomIn = function() {
-    this.setZoom(this.zoom_++);
+    this.setZoom(++this.zoom_);
 };
 
 ol.Map.prototype.zoomOut = function() {
-    this.setZoom(this.zoom_--);
+    this.setZoom(--this.zoom_);
 };
 
 /**