diff --git a/renderdocui/Code/FormatElement.cs b/renderdocui/Code/FormatElement.cs
index ab18ed6a0..e7edc5bee 100644
--- a/renderdocui/Code/FormatElement.cs
+++ b/renderdocui/Code/FormatElement.cs
@@ -101,7 +101,21 @@ namespace renderdocui.Code
         {
             get
             {
-                return format.compByteWidth * format.compCount * matrixdim;
+                uint vecSize = format.compByteWidth * format.compCount;
+
+                if (format.special)
+                {
+                    if (format.specialFormat == SpecialFormat.R5G5B5A1 ||
+                        format.specialFormat == SpecialFormat.R5G6B5 ||
+                        format.specialFormat == SpecialFormat.R4G4B4A4)
+                        vecSize = 2;
+
+                    if (format.specialFormat == SpecialFormat.R10G10B10A2 ||
+                        format.specialFormat == SpecialFormat.R11G11B10)
+                        vecSize = 4;
+                }
+
+                return vecSize * matrixdim;
             }
         }
 
diff --git a/renderdocui/Windows/BufferViewer.cs b/renderdocui/Windows/BufferViewer.cs
index 4f8834489..22230e12d 100644
--- a/renderdocui/Windows/BufferViewer.cs
+++ b/renderdocui/Windows/BufferViewer.cs
@@ -1714,7 +1714,7 @@ namespace renderdocui.Windows
                             var fmt = bufferFormats[el].format;
                             int byteWidth = (int)fmt.compByteWidth;
 
-                            int bytesToRead = (int)(fmt.compByteWidth * fmt.compCount);
+                            int bytesToRead = (int)bufferFormats[el].ByteSize;
 
                             byte[] bytes = read.ReadBytes(bytesToRead);
                             rawWriter.Write(bytes);