diff --git a/src/by/By.Hash.cs b/src/by/By.Hash.cs
index b52e52a..5836894 100644
--- a/src/by/By.Hash.cs
+++ b/src/by/By.Hash.cs
@@ -10,6 +10,8 @@ public partial class By : IBy
     {
         public static Types Hash<T>(T value)
         {
+            if (value == null) return Types.Null;
+            
             Type type = typeof(T) == typeof(Type) ? (Type)(object)value : value.GetType();
 
             if (type == typeof(sbyte)) return Types.Sbyte;