diff --git a/src/Umbraco.Core/Strings/LegacyShortStringHelper.cs b/src/Umbraco.Core/Strings/LegacyShortStringHelper.cs
index 552c16a5ac..83d0f25543 100644
--- a/src/Umbraco.Core/Strings/LegacyShortStringHelper.cs
+++ b/src/Umbraco.Core/Strings/LegacyShortStringHelper.cs
@@ -32,14 +32,14 @@ namespace Umbraco.Core.Strings
         }
 
         const string UmbracoValidAliasCharacters = "_-abcdefghijklmnopqrstuvwxyz1234567890";
-        const string UmbracoInvalidFirstCharacters = "01234567890";
+        const string UmbracoInvalidFirstCharacters = "0123456789";
 
         #endregion
 
         #region Short string services JavaScript
 
         const string SssjsValidCharacters = "_-abcdefghijklmnopqrstuvwxyz1234567890";
-        const string SssjsInvalidFirstCharacters = "01234567890";
+        const string SssjsInvalidFirstCharacters = "0123456789";
 
         private const string SssjsFormat = @"
 var UMBRACO_FORCE_SAFE_ALIAS = {0};
diff --git a/src/umbraco.cms/helpers/Casing.cs b/src/umbraco.cms/helpers/Casing.cs
index 4e06d1d7ab..1cf6eaf698 100644
--- a/src/umbraco.cms/helpers/Casing.cs
+++ b/src/umbraco.cms/helpers/Casing.cs
@@ -15,7 +15,7 @@ namespace umbraco.cms.helpers
         public const string VALID_ALIAS_CHARACTERS = "_-abcdefghijklmnopqrstuvwxyz1234567890";
 
         [Obsolete("Use Umbraco.Core.StringExtensions.UmbracoInvalidFirstCharacters instead")]
-        public const string INVALID_FIRST_CHARACTERS = "01234567890";
+        public const string INVALID_FIRST_CHARACTERS = "0123456789";
 
         /// <summary>
         /// A helper method to ensure that an Alias string doesn't contains any illegal characters