ICS File Viewer

How to use

1. 1Drop an .ics file onto the dropzone, click Choose file, or paste the raw source into the textarea. Click Load sample to see a worked example with a recurring meeting, an all-day event, a VTIMEZONE block, attendees, and a reminder.
2. 2Browse the calendar header for PRODID, version, method, and the X-WR-CALNAME label that most calendar apps use as the calendar title.
3. 3Switch tabs between Events, To-dos, Journals, Free / busy, Time zones, and Raw source to see each component type.
4. 4Open any event card to see start, end, duration, location, attendees with RSVP status, recurrence rule in plain English, and reminders.
5. 5Click Show raw on any event to view its original .ics block, then use Copy raw to save just that component, or copy the full source from the Raw source tab.

About this tool

ICS File Viewer opens any iCalendar (.ics) document in your browser and turns the raw RFC 5545 text into a friendly summary you can actually read. Drop an .ics file, paste the raw source, or click Load sample, and the parser unfolds continuation lines, walks every BEGIN/END block (VCALENDAR, VEVENT, VTODO, VJOURNAL, VFREEBUSY, VTIMEZONE, VALARM), and renders each event card with title, start and end, duration, location, status (confirmed, tentative, cancelled), time transparency (free or busy), visibility class (public, private, confidential), categories, organizer with email, the full attendee list with role and RSVP status, description, URL, and UID. DATE-TIME values are shown as they appear in the file, with the TZID parameter, the UTC Z suffix, or the floating local form labelled clearly so you know exactly what your calendar app will do with them. RRULE expressions are translated into plain English (Every week on Monday for 12 occurrences, Every year on the last Sunday of October, and so on) covering FREQ, INTERVAL, COUNT, UNTIL, BYDAY, BYMONTHDAY, BYMONTH, BYHOUR, BYSETPOS, and WKST. VALARM reminders are decoded with their action (DISPLAY, AUDIO, EMAIL), trigger duration (15 minutes before, 1 hour before, at time of event), and repeat count. A Notes panel surfaces parse warnings such as mismatched END markers, unrecognised components, or unbalanced blocks so broken invites are spotted before they reach your calendar. Tabs separate events, to-dos, journals, free-or-busy reports, and time zones; a Raw source tab shows the original text with a one-click copy. Useful for previewing email invites before importing, debugging calendar exports from custom apps, inspecting subscription feeds, diagnosing broken recurrence rules, auditing the attendee list on a multi-week meeting, and confirming the time zone of a cross-border invite without opening your live calendar. The file is read with the browser FileReader, parsed locally, and never uploaded.

Free to use. Works in your browser. No signup, no login.