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ICS Validator

Validate and audit iCalendar feeds for RFC 5545 compliance. Upload files or paste URLs to check for errors, missing UIDs, timezone issues, and more.

Universal Compatibility

Test Your Feed Now

Don't see your specific integration? Good news: If it exports an .ics or .ical feed, it works with Lokr.

  • Works with any iCalendar URL
  • Instant repair (no setup required)
  • Compatible with Outlook, Google, iOS

Upload or Paste URL

Paste the URL of your broken calendar feed

How It Works

What We Check

  • Missing or duplicate UIDs
  • Timezone definitions (VTIMEZONE)
  • RRULE validation (recurrence rules)
  • DTSTAMP presence
  • File truncation issues
  • Line ending normalization

Common Issues We Fix

  • Inject missing UIDs automatically
  • Add VTIMEZONE definitions for used timezones
  • Normalize RRULE UNTIL to UTC
  • Close truncated events
  • Deduplicate events
  • Propagate TZID from DTSTART to DTEND

Need Continuous Monitoring?

This tool is perfect for one-off validation. For automated repairs, continuous monitoring, and enterprise-grade reliability, check out Lokr Pro.