diff --git a/TagTool/Bitmaps/Utils/BitmapDecoder.cs b/TagTool/Bitmaps/Utils/BitmapDecoder.cs
index b1693983..261bd301 100644
--- a/TagTool/Bitmaps/Utils/BitmapDecoder.cs
+++ b/TagTool/Bitmaps/Utils/BitmapDecoder.cs
@@ -1483,7 +1483,7 @@ private static byte[] EncodeY8(byte[] data, int width, int height)
 
         public static List<byte[]> DecodeCubemap(byte[] bitmRaw, BitmapFormat format, int virtualWidth, int virtualHeight)
         {
-            int faceSize = virtualWidth * virtualHeight; // HACK DXT5 ONLY
+            int faceSize = (virtualWidth * virtualHeight * BitmapFormatUtils.GetBitsPerPixel(format)) / 8;
 
             List<byte[]> result = new List<byte[]>();//new byte[rawFaceSize * 6];