diff --git a/input.c b/input.c
index e3dc1805..be495066 100644
--- a/input.c
+++ b/input.c
@@ -1259,7 +1259,7 @@ keysym_is_modifier(xkb_keysym_t keysym)
 {
     return
         (keysym >= XKB_KEY_Shift_L && keysym <= XKB_KEY_Hyper_R) ||
-        /* libX11 only goes upto XKB_KEY_ISO_Level5_Lock. */
+        /* libX11 only goes up to XKB_KEY_ISO_Level5_Lock. */
         (keysym >= XKB_KEY_ISO_Lock && keysym <= XKB_KEY_ISO_Last_Group_Lock) ||
         keysym == XKB_KEY_Mode_switch ||
         keysym == XKB_KEY_Num_Lock;