diff --git a/src/ol/map.js b/src/ol/map.js
index e98aa3f1d1..5fe2ec60b2 100644
--- a/src/ol/map.js
+++ b/src/ol/map.js
@@ -15,7 +15,6 @@ goog.require('goog.events.MouseWheelHandler');
 goog.require('goog.events.MouseWheelHandler.EventType');
 goog.require('goog.fx.anim');
 goog.require('goog.fx.anim.Animated');
-goog.require('goog.math.Size');
 goog.require('goog.object');
 goog.require('ol.Array');
 goog.require('ol.Control');
@@ -24,6 +23,7 @@ goog.require('ol.Extent');
 goog.require('ol.LayerRenderer');
 goog.require('ol.Object');
 goog.require('ol.Projection');
+goog.require('ol.Size');
 goog.require('ol.TransformFunction');
 
 
@@ -372,11 +372,10 @@ ol.Map.prototype.getResolutionForExtent = function(extent) {
 
 
 /**
- * @return {goog.math.Size|undefined} Size.
+ * @return {ol.Size|undefined} Size.
  */
 ol.Map.prototype.getSize = function() {
-  return /** @type {goog.math.Size|undefined} */ (
-      this.get(ol.MapProperty.SIZE));
+  return /** @type {ol.Size|undefined} */ this.get(ol.MapProperty.SIZE);
 };
 
 
@@ -573,8 +572,7 @@ ol.Map.prototype.handleUserProjectionChanged = function() {
  * @protected
  */
 ol.Map.prototype.handleViewportResize = function() {
-  var size = new goog.math.Size(
-      this.target_.clientWidth, this.target_.clientHeight);
+  var size = new ol.Size(this.target_.clientWidth, this.target_.clientHeight);
   this.setSize(size);
 };
 
@@ -725,11 +723,11 @@ ol.Map.prototype.setResolution = function(resolution) {
 
 
 /**
- * @param {goog.math.Size} size Size.
+ * @param {ol.Size} size Size.
  */
 ol.Map.prototype.setSize = function(size) {
   var currentSize = this.getSize();
-  if (!goog.isDef(currentSize) || !goog.math.Size.equals(size, currentSize)) {
+  if (!goog.isDef(currentSize) || !currentSize.equals(size)) {
     this.set(ol.MapProperty.SIZE, size);
   }
 };
diff --git a/src/ol/rectangle.js b/src/ol/rectangle.js
index 2b099e899a..f35768e2c8 100644
--- a/src/ol/rectangle.js
+++ b/src/ol/rectangle.js
@@ -1,8 +1,8 @@
 goog.provide('ol.Rectangle');
 
 goog.require('goog.asserts');
-goog.require('goog.math.Size');
 goog.require('ol.Coordinate');
+goog.require('ol.Size');
 
 
 
@@ -90,10 +90,10 @@ ol.Rectangle.prototype.getHeight = function() {
 
 
 /**
- * @return {goog.math.Size} Size.
+ * @return {ol.Size} Size.
  */
 ol.Rectangle.prototype.getSize = function() {
-  return new goog.math.Size(this.getWidth(), this.getHeight());
+  return new ol.Size(this.getWidth(), this.getHeight());
 };
 
 
diff --git a/src/ol/size.js b/src/ol/size.js
new file mode 100644
index 0000000000..c751b14fae
--- /dev/null
+++ b/src/ol/size.js
@@ -0,0 +1,25 @@
+goog.provide('ol.Size');
+
+goog.require('goog.math.Size');
+
+
+
+/**
+ * @constructor
+ * @extends {goog.math.Size}
+ * @param {number} width Width.
+ * @param {number} height Height.
+ */
+ol.Size = function(width, height) {
+  goog.base(this, width, height);
+};
+goog.inherits(ol.Size, goog.math.Size);
+
+
+/**
+ * @param {ol.Size} size Size.
+ * @return {boolean} Equals.
+ */
+ol.Size.prototype.equals = function(size) {
+  return this.width == size.width && this.height == size.height;
+};
diff --git a/src/ol/tilebounds.js b/src/ol/tilebounds.js
index 58e1383064..2caa10da29 100644
--- a/src/ol/tilebounds.js
+++ b/src/ol/tilebounds.js
@@ -1,7 +1,6 @@
 goog.provide('ol.TileBounds');
 
 goog.require('goog.asserts');
-goog.require('goog.math.Size');
 goog.require('ol.Rectangle');
 goog.require('ol.TileCoord');
 
diff --git a/src/ol/tilegrid/openstreetmap.js b/src/ol/tilegrid/openstreetmap.js
index c3778fc55d..f5ffddc9d6 100644
--- a/src/ol/tilegrid/openstreetmap.js
+++ b/src/ol/tilegrid/openstreetmap.js
@@ -1,8 +1,8 @@
 goog.provide('ol.tilegrid.createOpenStreetMap');
 
-goog.require('goog.math.Size');
 goog.require('ol.Coordinate');
 goog.require('ol.Projection');
+goog.require('ol.Size');
 goog.require('ol.TileGrid');
 
 
@@ -21,7 +21,7 @@ ol.tilegrid.createOpenStreetMap = function(maxZoom) {
   var extent = ol.Projection.EPSG_3857_EXTENT;
   var origin = new ol.Coordinate(
       -ol.Projection.EPSG_3857_HALF_SIZE, ol.Projection.EPSG_3857_HALF_SIZE);
-  var tileSize = new goog.math.Size(256, 256);
+  var tileSize = new ol.Size(256, 256);
 
   return new ol.TileGrid(resolutions, extent, origin, tileSize);
 
diff --git a/src/ol/tilegrid/tilegrid.js b/src/ol/tilegrid/tilegrid.js
index 75406a104d..85fff11749 100644
--- a/src/ol/tilegrid/tilegrid.js
+++ b/src/ol/tilegrid/tilegrid.js
@@ -2,9 +2,9 @@ goog.provide('ol.TileGrid');
 
 goog.require('goog.array');
 goog.require('goog.asserts');
-goog.require('goog.math.Size');
 goog.require('ol.Coordinate');
 goog.require('ol.Extent');
+goog.require('ol.Size');
 goog.require('ol.TileBounds');
 goog.require('ol.TileCoord');
 
@@ -15,7 +15,7 @@ goog.require('ol.TileCoord');
  * @param {!Array.<number>} resolutions Resolutions.
  * @param {ol.Extent} extent Extent.
  * @param {ol.Coordinate|!Array.<ol.Coordinate>} origin Origin.
- * @param {goog.math.Size=} opt_tileSize Tile size.
+ * @param {ol.Size=} opt_tileSize Tile size.
  */
 ol.TileGrid = function(resolutions, extent, origin, opt_tileSize) {
 
@@ -63,10 +63,10 @@ ol.TileGrid = function(resolutions, extent, origin, opt_tileSize) {
 
   /**
    * @private
-   * @type {goog.math.Size}
+   * @type {ol.Size}
    */
   this.tileSize_ = goog.isDef(opt_tileSize) ?
-      opt_tileSize : new goog.math.Size(256, 256);
+      opt_tileSize : new ol.Size(256, 256);
 
 };
 
@@ -214,7 +214,7 @@ ol.TileGrid.prototype.getTileCoordResolution = function(tileCoord) {
 
 
 /**
- * @return {goog.math.Size} Tile size.
+ * @return {ol.Size} Tile size.
  */
 ol.TileGrid.prototype.getTileSize = function() {
   return this.tileSize_;
diff --git a/src/ol/tilegrid/tilegrid_test.js b/src/ol/tilegrid/tilegrid_test.js
index 0b609390fd..84f904a17c 100644
--- a/src/ol/tilegrid/tilegrid_test.js
+++ b/src/ol/tilegrid/tilegrid_test.js
@@ -1,7 +1,7 @@
-goog.require('goog.math.Size');
 goog.require('goog.testing.jsunit');
 goog.require('ol.Coordinate');
 goog.require('ol.Extent');
+goog.require('ol.Size');
 goog.require('ol.TileCoord');
 goog.require('ol.TileGrid');
 
@@ -18,7 +18,7 @@ function setUp() {
   extent = new ol.Extent(0, 0, 100000, 100000);
   origin = new ol.Coordinate(0, 0);
   origins = [];
-  tileSize = new goog.math.Size(100, 100);
+  tileSize = new ol.Size(100, 100);
 }
 
 
diff --git a/src/ol/webgl/tilelayerrenderer.js b/src/ol/webgl/tilelayerrenderer.js
index 8a700abf1d..4ef5af132c 100644
--- a/src/ol/webgl/tilelayerrenderer.js
+++ b/src/ol/webgl/tilelayerrenderer.js
@@ -9,6 +9,7 @@ goog.require('goog.events.EventType');
 goog.require('goog.vec.Mat4');
 goog.require('goog.webgl');
 goog.require('ol.Coordinate');
+goog.require('ol.Size');
 goog.require('ol.TileLayer');
 goog.require('ol.webgl.LayerRenderer');
 goog.require('ol.webgl.shader.Fragment');
@@ -122,7 +123,7 @@ ol.webgl.TileLayerRenderer = function(map, tileLayer) {
 
   /**
    * @private
-   * @type {goog.math.Size}
+   * @type {ol.Size}
    */
   this.framebufferSize_ = null;
 
@@ -230,12 +231,12 @@ ol.webgl.TileLayerRenderer.prototype.redraw = function() {
   var tileBoundsSize = tileBounds.getSize();
   var tileSize = tileGrid.getTileSize();
 
-  var framebufferSize = new goog.math.Size(
+  var framebufferSize = new ol.Size(
       tileSize.width * tileBoundsSize.width,
       tileSize.height * tileBoundsSize.height);
 
   if (goog.isNull(this.framebufferSize_) ||
-      !goog.math.Size.equals(this.framebufferSize_, framebufferSize)) {
+      !this.framebufferSize_.equals(framebufferSize)) {
 
     gl.deleteFramebuffer(this.framebuffer_);
     gl.deleteRenderbuffer(this.renderbuffer_);