diff --git a/src/js/service/palette/reader/PaletteGplReader.js b/src/js/service/palette/reader/PaletteGplReader.js
index c2631654..e8be9f8c 100644
--- a/src/js/service/palette/reader/PaletteGplReader.js
+++ b/src/js/service/palette/reader/PaletteGplReader.js
@@ -18,6 +18,6 @@
       b : parseInt(matches[3], 10)
     });
 
-    return color.toRgbString();
+    return color.toHexString();
   };
 })();
diff --git a/src/js/service/palette/reader/PalettePalReader.js b/src/js/service/palette/reader/PalettePalReader.js
index 6513d7e6..a906fab8 100644
--- a/src/js/service/palette/reader/PalettePalReader.js
+++ b/src/js/service/palette/reader/PalettePalReader.js
@@ -11,7 +11,9 @@
 
   ns.PalettePalReader.prototype.extractColorFromLine = function (line) {
     var matches = line.match(RE_COLOR_LINE);
-    var color = 'rgb(' + matches[1] + ',' + matches[2] + ',' + matches[3] + ')';
-    return color;
+    var rgbColor = 'rgb(' + matches[1] + ',' + matches[2] + ',' + matches[3] + ')';
+    var color = window.tinycolor(rgbColor);
+
+    return color.toHexString();
   };
 })();
diff --git a/src/js/service/palette/reader/PaletteTxtReader.js b/src/js/service/palette/reader/PaletteTxtReader.js
index 94e32aab..dbe532a3 100644
--- a/src/js/service/palette/reader/PaletteTxtReader.js
+++ b/src/js/service/palette/reader/PaletteTxtReader.js
@@ -12,6 +12,6 @@
   ns.PaletteTxtReader.prototype.extractColorFromLine = function (line) {
     var matches = line.match(RE_COLOR_LINE);
     var color = '#' + matches[1] + matches[2] + matches[3];
-    return color;
+    return color.toLowerCase();
   };
 })();
diff --git a/src/js/tools/drawing/Lighten.js b/src/js/tools/drawing/Lighten.js
index 3f6e7254..f0cfb98e 100644
--- a/src/js/tools/drawing/Lighten.js
+++ b/src/js/tools/drawing/Lighten.js
@@ -73,6 +73,6 @@
     usedPixels[key] = true;
 
     // Convert tinycolor color to string format.
-    return color.toRgbString();
+    return color.toHexString();
   };
 })();
diff --git a/src/js/widgets/ColorsList.js b/src/js/widgets/ColorsList.js
index 3966635f..e5041d6e 100644
--- a/src/js/widgets/ColorsList.js
+++ b/src/js/widgets/ColorsList.js
@@ -71,10 +71,10 @@
   };
 
   ns.ColorsList.prototype.onColorUpdated_ = function (color) {
-    var rgbColor = color.toRgbString();
-    this.colorPreviewEl.style.background = rgbColor;
+    var strColor = color.toHexString();
+    this.colorPreviewEl.style.background = strColor;
     if (this.palette) {
-      this.palette.set(this.selectedIndex, rgbColor);
+      this.palette.set(this.selectedIndex, strColor);
       this.refreshColorElement_(this.selectedIndex);
     }
   };
diff --git a/src/js/worker/framecolors/FrameColorsWorker.js b/src/js/worker/framecolors/FrameColorsWorker.js
index 787f0433..45a79479 100644
--- a/src/js/worker/framecolors/FrameColorsWorker.js
+++ b/src/js/worker/framecolors/FrameColorsWorker.js
@@ -17,7 +17,7 @@
         var hexRe = (/^#([a-f0-9]{3}){1,2}$/i);
         var rgbRe = (/^rgb\((\d{1,3}),(\d{1,3}),(\d{1,3})\)$/i);
         if (hexRe.test(color)) {
-          return color.toUpperCase();
+          return color.toLowerCase();
         } else if (rgbRe.test(color)) {
           var exec = rgbRe.exec(color);
           return rgbToHex(exec[1] * 1, exec[2] * 1, exec[3] * 1);