diff --git a/helpers/ical.ts b/helpers/ical.ts
index 509e51d..7bf600f 100644
--- a/helpers/ical.ts
+++ b/helpers/ical.ts
@@ -1,19 +1,33 @@
-import { createEvents } from 'ics'
+import { createEvents, EventStatus } from 'ics'
 import { BookingDocument } from '../db/booking'
+import { BOOKING_STATUS } from '../db/bookingStatus'
+import { getBaseURL } from './url'
+
+function convertDay(value: string): [number, number, number] {
+  const parts = value.split('-')
+  if (parts.length !== 3) {
+    throw new Error('faile converting day')
+  }
+  return [Number(parts[0]), Number(parts[1]), Number(parts[2])]
+}
 
 export function generateBookedCalendar(bookings: BookingDocument[]) {
   const events = bookings.map((booking) => ({
+    start: convertDay(booking.days[0]),
+    end: convertDay(booking.days[booking.days.length - 1]),
     title: `Buchung ${booking.booker.name}`,
     description: `UUID: ${booking.uuid}
-Link: http://${process.env.VERCEL_URL}/booking/${booking.uuid}`,
-    start: booking.days[0].split('-'),
-    end: booking.days[booking.days.length - 1].split('-'),
+Link: ${getBaseURL()}/booking/${booking.uuid}`,
+    status:
+      booking.status === BOOKING_STATUS.CONFIRMED
+        ? ('CONFIRMED' as EventStatus)
+        : ('TENTATIVE' as EventStatus),
   }))
-  // ts-ignore
+
   const { error, value } = createEvents(events)
 
   if (error) {
-    throw new Error(error)
+    throw error
   }
 
   return value