diff --git a/dist/smartstring.domain.js b/dist/smartstring.domain.js
index 0201387..82ccf8b 100644
--- a/dist/smartstring.domain.js
+++ b/dist/smartstring.domain.js
@@ -32,7 +32,7 @@ var Domain = (function () {
 }());
 exports.Domain = Domain;
 var domainRegex = function (stringArg) {
-    var regexString = /([a-zA-Z0-9]*)\.{0,1}([a-zA-Z0-9]*)\.{0,1}([a-zA-Z0-9]*)\.{0,1}([a-zA-Z0-9]*)\.{0,1}([a-zA-Z0-9]*)\.{0,1}$/;
+    var regexString = /([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}$/;
     var regexMatches = regexString.exec(stringArg);
     regexMatches.reverse(); //make sure we build the domain from toplevel to subdomain (reversed order)
     regexMatches.pop(); // pop the last element, which is, since we reversed the Array, the full String of matched elements
@@ -52,4 +52,4 @@ var protocolRegex = function (stringArg) {
     }
 };
 
-//# 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mluZ0FyZyAhPSBcIlwiKTtcbiAgICB9KTtcbiAgICByZXR1cm4gcmVnZXhNYXRjaGVzRmlsdGVyZWQ7XG59O1xuXG5sZXQgcHJvdG9jb2xSZWdleCA9IGZ1bmN0aW9uKHN0cmluZ0FyZzpzdHJpbmcpe1xuICAgIGxldCByZWdleFN0cmluZyA9IC9eKFthLXpBLVowLTldKik6XFwvXFwvLztcbiAgICBsZXQgcmVnZXhNYXRjaGVzID0gcmVnZXhTdHJpbmcuZXhlYyhzdHJpbmdBcmcpO1xuICAgIGlmKHJlZ2V4TWF0Y2hlcyl7XG4gICAgICAgIHJldHVybiByZWdleE1hdGNoZXNbMV07XG4gICAgfSBlbHNlIHtcbiAgICAgICAgcmV0dXJuIHVuZGVmaW5lZDtcbiAgICB9XG59Il19
+//# sourceMappingURL=data:application/json;charset=utf8;base64,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
diff --git a/ts/smartstring.domain.ts b/ts/smartstring.domain.ts
index ef92eee..f40eeb4 100644
--- a/ts/smartstring.domain.ts
+++ b/ts/smartstring.domain.ts
@@ -42,7 +42,7 @@ export class Domain {
 
 
 let domainRegex = function(stringArg:string){
-    let regexString = /([a-zA-Z0-9]*)\.{0,1}([a-zA-Z0-9]*)\.{0,1}([a-zA-Z0-9]*)\.{0,1}([a-zA-Z0-9]*)\.{0,1}([a-zA-Z0-9]*)\.{0,1}$/;
+    let regexString = /([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}$/;
     let regexMatches = regexString.exec(stringArg);
     regexMatches.reverse(); //make sure we build the domain from toplevel to subdomain (reversed order)
     regexMatches.pop(); // pop the last element, which is, since we reversed the Array, the full String of matched elements