diff --git a/modules/RichSiteSummary/Data/Post.cs b/modules/RichSiteSummary/Data/Post.cs
index cf1dd89..6c72a89 100644
--- a/modules/RichSiteSummary/Data/Post.cs
+++ b/modules/RichSiteSummary/Data/Post.cs
@@ -69,6 +69,7 @@ namespace Kruzya.TelegramBot.RichSiteSummary.Data
         /// The URI where this post is located in web.
         /// </summary>
         [Required]
+        [MaxLength(256)]
         public string Url { get; set; }
         
         /// <summary>
@@ -104,4 +105,4 @@ namespace Kruzya.TelegramBot.RichSiteSummary.Data
             }
         }
     }
-}
\ No newline at end of file
+}