diff --git a/config.def.h b/config.def.h
index f7822d2..5a18854 100644
--- a/config.def.h
+++ b/config.def.h
@@ -12,7 +12,7 @@
 #define SELFGCOLOR		"#ffffff"
 
 /* tagging */
-const char *tags[] = { "1", "2", "3", "4", "5", "6", "7", "8", "www", NULL };
+const char *tags[] = { "1", "2", "3", "4", "5", "6", "7", "8", "www" };
 Rule rules[] = {
 	/* class:instance:title regex	tags regex	isfloating */
 	{ "Firefox",			"www",		False },
diff --git a/dwm.c b/dwm.c
index 6a21d3f..c9495ec 100644
--- a/dwm.c
+++ b/dwm.c
@@ -1467,7 +1467,7 @@ setup(void) {
 
 	/* init tags */
 	compileregs();
-	for(ntags = 0; tags[ntags]; ntags++);
+	ntags = sizeof tags / sizeof tags[0];
 	seltags = emallocz(sizeof(Bool) * ntags);
 	seltags[0] = True;