diff --git a/main.c b/main.c
index ba5e2e0..067f383 100644
--- a/main.c
+++ b/main.c
@@ -101,6 +101,7 @@ setup(void) {
 	cursor[CurResize] = XCreateFontCursor(dpy, XC_sizing);
 	cursor[CurMove] = XCreateFontCursor(dpy, XC_fleur);
 	/* init modifier map */
+	numlockmask = 0;
 	modmap = XGetModifierMapping(dpy);
 	for (i = 0; i < 8; i++) {
 		for (j = 0; j < modmap->max_keypermod; j++) {