diff --git a/x.c b/x.c
index aa09997..b36fb8c 100644
--- a/x.c
+++ b/x.c
@@ -818,7 +818,7 @@ xloadcols(void)
 int
 xgetcolor(int x, unsigned char *r, unsigned char *g, unsigned char *b)
 {
-	if (!BETWEEN(x, 0, dc.collen))
+	if (!BETWEEN(x, 0, dc.collen - 1))
 		return 1;
 
 	*r = dc.col[x].color.red >> 8;
@@ -833,7 +833,7 @@ xsetcolorname(int x, const char *name)
 {
 	Color ncolor;
 
-	if (!BETWEEN(x, 0, dc.collen))
+	if (!BETWEEN(x, 0, dc.collen - 1))
 		return 1;
 
 	if (!xloadcolor(x, name, &ncolor))