diff --git a/isso/__init__.py b/isso/__init__.py
index 7122ff7..1f70390 100644
--- a/isso/__init__.py
+++ b/isso/__init__.py
@@ -183,7 +183,7 @@ def make_app(conf=None, threading=True, multiprocessing=False, uwsgi=False):
 
     wrapper.append(partial(wsgi.CORSMiddleware,
         origin=origin(isso.conf.getiter("general", "host")),
-        allowed=("Origin", "Content-Type"), exposed=("X-Set-Cookie", )))
+        allowed=("Origin", "Content-Type"), exposed=("X-Set-Cookie", "Date")))
 
     wrapper.extend([wsgi.SubURI, ProxyFix])
 
diff --git a/isso/js/app/api.js b/isso/js/app/api.js
index 24de165..f0bc3a8 100644
--- a/isso/js/app/api.js
+++ b/isso/js/app/api.js
@@ -1,4 +1,4 @@
-define(["app/lib/promise"], function(Q) {
+define(["app/lib/promise", "app/globals"], function(Q, globals) {
 
     "use strict";
 
@@ -41,8 +41,9 @@ define(["app/lib/promise"], function(Q) {
 
         function onload() {
 
-            var cookie = xhr.getResponseHeader("X-Set-Cookie");
+            globals.offset.update(new Date(xhr.getResponseHeader("Date")));
 
+            var cookie = xhr.getResponseHeader("X-Set-Cookie");
             if (cookie && cookie.match(/^isso-/)) {
                 document.cookie = cookie;
             }
diff --git a/isso/js/app/globals.js b/isso/js/app/globals.js
new file mode 100644
index 0000000..b3efe9d
--- /dev/null
+++ b/isso/js/app/globals.js
@@ -0,0 +1,21 @@
+define(function() {
+    "use strict";
+
+    var Offset = function() {
+        this.values = [];
+    };
+
+    Offset.prototype.update = function(remoteTime) {
+        this.values.push((new Date()).getTime() - remoteTime);
+    };
+
+    Offset.prototype.localTime = function() {
+        return new Date((new Date()).getTime() + this.values.reduce(
+            function(a, b) { return a + b; }) / this.values.length);
+    };
+
+    return {
+        offset: new Offset()
+    };
+
+});
\ No newline at end of file
diff --git a/isso/js/app/isso.js b/isso/js/app/isso.js
index d2b2077..fff7552 100644
--- a/isso/js/app/isso.js
+++ b/isso/js/app/isso.js
@@ -1,7 +1,7 @@
 /* Isso – Ich schrei sonst!
  */
-define(["app/text/html", "app/dom", "app/utils", "app/config", "app/api", "app/markup", "app/i18n", "app/lib"],
-    function(templates, $, utils, config, api, Mark, i18n, lib) {
+define(["app/text/html", "app/dom", "app/utils", "app/config", "app/api", "app/markup", "app/i18n", "app/lib", "app/globals"],
+    function(templates, $, utils, config, api, Mark, i18n, lib, globals) {
 
     "use strict";
 
@@ -100,7 +100,7 @@ define(["app/text/html", "app/dom", "app/utils", "app/config", "app/api", "app/m
         // update datetime every 60 seconds
         var refresh = function() {
             $(".permalink > date", el).textContent = utils.ago(
-                new Date(parseInt(comment.created, 10) * 1000));
+                globals.offset.localTime(), new Date(parseInt(comment.created, 10) * 1000));
             setTimeout(refresh, 60*1000);
         };
 
diff --git a/isso/js/app/utils.js b/isso/js/app/utils.js
index dfe737c..7c8f1bf 100644
--- a/isso/js/app/utils.js
+++ b/isso/js/app/utils.js
@@ -5,9 +5,9 @@ define(["app/markup"], function(Mark) {
         return (document.cookie.match('(^|; )' + cookie + '=([^;]*)') || 0)[2];
     };
 
-    var ago = function(date) {
+    var ago = function(localTime, date) {
 
-        var diff = (((new Date()).getTime() - date.getTime()) / 1000),
+        var diff = ((localTime.getTime() - date.getTime()) / 1000),
             day_diff = Math.floor(diff / 86400);
 
         if (isNaN(day_diff) || day_diff < 0) {