diff --git a/src/utils.js b/src/utils.js
index 64a24e3..d52576f 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -22,10 +22,28 @@ function tileToLat(tileY, zoom) {
   return (180.0 / Math.PI) * Math.atan(0.5 * (Math.exp(n) - Math.exp(-n)));
 }
 
-export const getPublicUrl = (publicUrl, req) => publicUrl || `${req.protocol}://${req.headers.host}/`;
+/**
+ * Generate new URL object
+ * @param req
+ * @params {object} req - Express request
+ * @returns {URL} object
+ */
+const getUrlObject = (req) => {
+  const urlObject = new URL(`${req.protocol}://${req.headers.host}/`);
+  // support overriding hostname by sending X-Forwarded-Host http header
+  urlObject.hostname = req.hostname;
+  return urlObject;
+};
+
+export const getPublicUrl = (publicUrl, req) => {
+  if (publicUrl) {
+    return publicUrl;
+  }
+  return getUrlObject(req).toString();
+};
 
 export const getTileUrls = (req, domains, path, format, publicUrl, aliases) => {
-
+  const urlObject = getUrlObject(req);
   if (domains) {
     if (domains.constructor === String && domains.length > 0) {
       domains = domains.split(',');