ICS Validator
Validate an iCal / iCalendar (.ics) file and get a clear list of issues that commonly break imports
or cause events to show at the wrong time.
What this ICS validator checks
-
Required structure and fields (
VCALENDAR/VEVENT,DTSTART,UID,VERSION) -
Timezone correctness (
TZID, missing/brokenVTIMEZONE, DST drift) - Formatting that breaks imports (line folding, encoding, invalid characters)
Popular fixes & guides
- ICS validator guide: validate ICS and fix errors
- What is an ICS (iCal / iCalendar) file?
- ICS file won’t import (Google Calendar / Outlook)
- Common ICS import errors by calendar app
- Events at the wrong time (TZID/VTIMEZONE)
- TZID=EST is invalid (use America/New_York)
- Outlook missing VTIMEZONE
- iCal validator: validate iCalendar (.ics) files
Fastest path
Upload your file to /fix, review the first error, and download a repaired file when fixes
are available.