diff --git a/src/js/tools/drawing/ColorSwap.js b/src/js/tools/drawing/ColorSwap.js
index 20184500..fa853172 100644
--- a/src/js/tools/drawing/ColorSwap.js
+++ b/src/js/tools/drawing/ColorSwap.js
@@ -28,7 +28,6 @@
 
       var allLayers = pskl.utils.UserAgent.isMac ?  event.metaKey : event.ctrlKey;
       var allFrames = event.shiftKey;
-
       this.swapColors_(oldColor, newColor, allLayers, allFrames);
 
       this.raiseSaveStateEvent({
@@ -56,8 +55,10 @@
   };
 
   ns.ColorSwap.prototype.applyToolOnFrame_ = function (frame, oldColor, newColor) {
+    oldColor = pskl.utils.colorToInt(oldColor);
+    newColor = pskl.utils.colorToInt(newColor);
     frame.forEachPixel(function (color, col, row) {
-      if (color && color == oldColor) {
+      if (color !== null && color == oldColor) {
         frame.setPixel(col, row, newColor);
       }
     });
diff --git a/src/js/utils/PixelUtils.js b/src/js/utils/PixelUtils.js
index c67c5d49..667d7a48 100644
--- a/src/js/utils/PixelUtils.js
+++ b/src/js/utils/PixelUtils.js
@@ -146,6 +146,10 @@
        *  13. Continue looping until Q is exhausted.
        *  14. Return.
        */
+      if (typeof replacementColor == 'string') {
+        replacementColor = pskl.utils.colorToInt(replacementColor);
+      }
+
       var targetColor;
       try {
         targetColor = frame.getPixel(col, row);
@@ -153,7 +157,7 @@
         // Frame out of bound exception.
       }
 
-      if (targetColor == replacementColor) {
+      if (targetColor === null || targetColor == replacementColor) {
         return;
       }
 
@@ -162,7 +166,7 @@
         row : row
       };
       var paintedPixels = pskl.PixelUtils.visitConnectedPixels(startPixel, frame, function (pixel) {
-        if (frame.containsPixel(pixel.col, pixel.row) && frame.getPixel(pixel.col, pixel.row) == targetColor) {
+        if (frame.getPixel(pixel.col, pixel.row) == targetColor) {
           frame.setPixel(pixel.col, pixel.row, replacementColor);
           return true;
         }