--- a/tools/lib64util.c	Sat Jun 15 09:16:28 2019 +0300
+++ b/tools/lib64util.c	Sat Jun 15 14:14:40 2019 +0300
@@ -139,7 +139,11 @@
 
 void argShowC64PaletteHelp(FILE *fp)
 {
-    fprintf(fp, "\nAvailable C64 palettes:\n");
+    fprintf(fp,
+        "\n"
+        "Available C64 palettes (-p <name>):\n"
+        "-----------------------------------\n");
+
     for (int n = 0; n < ndmC64DefaultPalettes; n++)
     {
         DMC64Palette *pal = &dmC64DefaultPalettes[n];
@@ -147,6 +151,25 @@
             "%-10s | %s\n",
             pal->name, pal->desc);
     }
+
+    fprintf(fp,
+        "\n"
+        "Instead one of the internal palettes, you can\n"
+        "also specify an external palette file.\n"
+        "Supported palette file formats are:\n"
+        "-----------------------------------\n"
+        );
+
+    for (int n = 0; n < ndmPaletteFormatList; n++)
+    {
+        DMPaletteFormat *fmt = &dmPaletteFormatList[n];
+        if (fmt->flags & DM_FMT_RD)
+        {
+            fprintf(fp,
+                "%-6s | %s\n",
+                fmt->fext, fmt->name);
+        }
+    }
     fprintf(fp, "\n");
 }