diff --git a/libs/util/include/psemek/util/hash_table.hpp b/libs/util/include/psemek/util/hash_table.hpp
index ae0d1acc..b947a866 100644
--- a/libs/util/include/psemek/util/hash_table.hpp
+++ b/libs/util/include/psemek/util/hash_table.hpp
@@ -475,6 +475,12 @@ namespace psemek::util
 			return find(key) != end();
 		}
 
+		template <typename Key1>
+		std::size_t count(Key1 const & key) const
+		{
+			return contains(key) ? 1 : 0;
+		}
+
 		bool erase(iterator const & it)
 		{
 			impl_.erase(it.internal());
@@ -606,6 +612,12 @@ namespace psemek::util
 			return find(key) != end();
 		}
 
+		template <typename Key1>
+		std::size_t count(Key1 const & key) const
+		{
+			return contains(key) ? 1 : 0;
+		}
+
 		bool erase(iterator const & it)
 		{
 			impl_.erase(it.internal());