diff --git a/int2048.h b/int2048.h
index 9eca7bb..279576d 100644
--- a/int2048.h
+++ b/int2048.h
@@ -65,6 +65,9 @@ public:
   int2048 &operator/=(const int2048 &);
   friend int2048 operator/(int2048, const int2048 &);
 
+  int2048 &operator%=(const int2048 &);
+  friend int2048 operator%(int2048, const int2048 &);
+
   friend std::istream &operator>>(std::istream &, int2048 &);
   friend std::ostream &operator<<(std::ostream &, const int2048 &);