Calendar files, explained
Guides for getting it right.
Clear answers for opening, converting, repairing, importing and sharing calendar files—grounded in the iCalendar standard and tested against real calendar problems.
Open an ICS file without importing
Learn how to open and read an ICS calendar file safely on any device without adding its events to Google Calendar, Outlook or Apple Calendar.
Read the guide →Fix Google Calendar ICS import errors
Diagnose and repair ICS files that Google Calendar cannot import, including processed-zero-events, invalid format, file-size and timezone problems.
Read the guide →Convert CSV to ICS correctly
Convert spreadsheet rows into an ICS calendar with correct column mapping, date formats, timezones, all-day events and validation.
Read the guide →Understand iCalendar recurrence rules
Understand how repeating ICS events work, including DTSTART, RRULE, RDATE, EXDATE, RECURRENCE-ID, COUNT, UNTIL and recurring exceptions.
Read the guide →Understand ICS timezones
Learn the difference between floating time, UTC and TZID in ICS files, and prevent calendar events from shifting during import or daylight saving time.
Read the guide →Merge ICS files without duplicates
Combine multiple ICS calendar files safely while preserving event identities, recurring exceptions and timezones and avoiding duplicate imports.
Read the guide →Check personal data in an ICS file
See what private information an ICS file can reveal, including names, notes, locations, attendees, links, identifiers and schedule patterns.
Read the guide →Import ICS into major calendar apps
Step-by-step instructions for importing ICS files into Google Calendar, Outlook and Apple Calendar, with duplicate, subscription and troubleshooting advice.
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