diff --git a/src/ex_cmds.c b/src/ex_cmds.c
index 9da5c09..1d0a385 100644
--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -365,8 +365,8 @@
     long	deleted;
     colnr_T	start_col;
     colnr_T	end_col;
-    int		sort_oct;		/* sort on octal number */
-    int		sort_hex;		/* sort on hex number */
+    int		sort_what = 0;
+    int		format_found = 0;
 
     /* Sorting one line is really quick! */
     if (count <= 1)
@@ -381,7 +381,7 @@
     if (nrs == NULL)
 	goto sortend;
 
-    sort_abort = sort_ic = sort_rx = sort_nr = sort_oct = sort_hex = 0;
+    sort_abort = sort_ic = sort_rx = sort_nr = 0;
 
     for (p = eap->arg; *p != NUL; ++p)
     {
@@ -392,11 +392,25 @@
 	else if (*p == 'r')
 	    sort_rx = TRUE;
 	else if (*p == 'n')
+	{
 	    sort_nr = 2;
+	    ++format_found;
+	}
+	else if (*p == 'b')
+	{
+	    sort_what = STR2NR_BIN + STR2NR_FORCE;
+	    ++format_found;
+	}
 	else if (*p == 'o')
-	    sort_oct = 2;
+	{
+	    sort_what = STR2NR_OCT + STR2NR_FORCE;
+	    ++format_found;
+	}
 	else if (*p == 'x')
-	    sort_hex = 2;
+	{
+	    sort_what = STR2NR_HEX + STR2NR_FORCE;
+	    ++format_found;
+	}
 	else if (*p == 'u')
 	    unique = TRUE;
 	else if (*p == '"')	/* comment start */
@@ -439,15 +453,15 @@
 	}
     }
 
-    /* Can only have one of 'n', 'o' and 'x'. */
-    if (sort_nr + sort_oct + sort_hex > 2)
+    /* Can only have one of 'n', 'b', 'o' and 'x'. */
+    if (format_found > 1)
     {
 	EMSG(_(e_invarg));
 	goto sortend;
     }
 
     /* From here on "sort_nr" is used as a flag for any number sorting. */
-    sort_nr += sort_oct + sort_hex;
+    sort_nr += sort_what;
 
     /*
      * Make an array with all line numbers.  This avoids having to copy all
@@ -489,8 +503,10 @@
 	    *s2 = NUL;
 	    /* Sorting on number: Store the number itself. */
 	    p = s + start_col;
-	    if (sort_hex)
+	    if (sort_what & STR2NR_HEX)
 		s = skiptohex(p);
+	    else if (sort_what & STR2NR_BIN)
+		s = skiptobin(p);
 	    else
 		s = skiptodigit(p);
 	    if (s > p && s[-1] == '-')
@@ -499,8 +515,8 @@
 		/* empty line should sort before any number */
 		nrs[lnum - eap->line1].start_col_nr = -MAXLNUM;
 	    else
-		vim_str2nr(s, NULL, NULL, sort_oct, sort_hex,
-				  &nrs[lnum - eap->line1].start_col_nr, NULL, 0);
+		vim_str2nr(s, NULL, NULL, sort_what,
+			       &nrs[lnum - eap->line1].start_col_nr, NULL, 0);
 	    *s2 = c;
 	}
 	else