diff --git a/index.js b/index.js
index 3ea3d20..b98a37f 100644
--- a/index.js
+++ b/index.js
@@ -11,10 +11,10 @@ module.exports = isUrl;
  * Use two levels of REs to avoid REDOS.
  */
 
-var protocolAndDomainRE = /^(?:\w+:)?\/\/(\S+)$/;
+const protocolAndDomainRE = /^(?:\w+:)?\/\/(\S+)$/;
 
-var localhostDomainRE = /^localhost[\:?\d]*(?:[^\:?\d]\S*)?$/
-var nonLocalhostDomainRE = /^[^\s\.]+\.\S{2,}$/;
+const localhostDomainRE = /^localhost[\:?\d]*(?:[^\:?\d]\S*)?$/
+const nonLocalhostDomainRE = /^[^\s\.]+\.\S{2,}$/;
 
 /**
  * Loosely validate a URL `string`.
@@ -28,12 +28,12 @@ function isUrl(string){
     return false;
   }
 
-  var match = string.match(protocolAndDomainRE);
+  const match = string.match(protocolAndDomainRE);
   if (!match) {
     return false;
   }
 
-  var everythingAfterProtocol = match[1];
+  const everythingAfterProtocol = match[1];
   if (!everythingAfterProtocol) {
     return false;
   }