diff --git a/ttyclock.c b/ttyclock.c
index 3c4d7ce..f656c1e 100644
--- a/ttyclock.c
+++ b/ttyclock.c
@@ -192,7 +192,7 @@ update_hour(void)
      ihour = ttyclock->tm->tm_hour;
 
      if(ttyclock->option.twelve)
-          ttyclock->meridiem = ((ihour > 12) ? PMSIGN : AMSIGN);
+          ttyclock->meridiem = ((ihour >= 12) ? PMSIGN : AMSIGN);
      else
           ttyclock->meridiem = "\0";