diff --git a/lib/format.js b/lib/format.js
index a3958fd..badf53b 100644
--- a/lib/format.js
+++ b/lib/format.js
@@ -1,24 +1,8 @@
 module.exports = {
   formatArray,
-  formatDate,
   formatText
 };
 
-
-function formatDate(date) {
-  return [
-    date.getFullYear(),
-    pad(date.getMonth() + 1),
-    pad(date.getDate()),
-    'T',
-    pad(date.getHours()),
-    pad(date.getMinutes()),
-    pad(date.getSeconds()),
-  ].join('');
-
-  function pad(n) { return n.toString().padStart(2, 0); }
-}
-
 function formatArray(arr) {
   return arr.join(';');
 }
diff --git a/lib/ical.js b/lib/ical.js
index b4600fe..3a06285 100644
--- a/lib/ical.js
+++ b/lib/ical.js
@@ -1,5 +1,5 @@
 const { v5: uuid } = require('uuid');
-const { formatDate, formatArray } = require("./format");
+const { formatArray } = require("./format");
 const property = require("./property");
 
 exports = module.exports = ical;
@@ -15,14 +15,13 @@ function id2uuid(id, day) {
   return uuid(id, NAMESPACE) + '@furkot.com';
 }
 
-const offset = new Date().getTimezoneOffset() * 60 * 1000;
-
 function ts2date(ts) {
-  return formatDate(new Date(ts + offset));
+  // remove dashes and colons and strip milliseconds
+  return new Date(ts).toISOString().replace(/[-:]/g, '').slice(0, -5);
 }
 
 function* ical({ metadata, routes }) {
-  const dtstamp = formatDate(new Date());
+  const dtstamp = ts2date(Date.now());
 
   yield* property('BEGIN', 'VCALENDAR');
   yield* property('VERSION', '2.0');