iCalendar Events, Time Zones & Recurrence
Inspect UTF-8 iCalendar 2.0 events, source/display/UTC times and daylight-saving offsets. Shows RRULE fields and original RDATE, EXDATE and RECURRENCE-ID properties; preserves unknown properties and alarms in ICS. No event recurrence expansion or full RFC conformance certification.
About this icalendar events, time zones & recurrence
Inspect UTF-8 iCalendar 2.0 events, source/display/UTC times and daylight-saving offsets. Shows RRULE fields and original RDATE, EXDATE and RECURRENCE-ID properties; preserves unknown properties and alarms in ICS. No event recurrence expansion or full RFC conformance certification Parses and structures office document payloads locally in memory without transmitting private company files to external servers.
Document parsing & data extraction pipeline
Inspects, parses, and converts open publishing and scheduling formats conforming to IDPF EPUB 3.2 / 3.3 specifications, IETF RFC 5545 (iCalendar - .ics), and RFC 6350 (vCard v4.0 - .vcf). EPUB tools unpack the OCF (Open Container Format) ZIP package, parsing META-INF/container.xml and the OPF (Open Packaging Format) package document to extract Dublin Core metadata (dc:title, dc:creator, dc:identifier), spine order, manifest items, and table of contents (NCX / Nav doc), converting chapters to Markdown.
Worked document extraction example
Scenario: Execute iCalendar Events, Time Zones & Recurrence with sample data to verify transformation accuracy and output formatting.
Sample input:
Processing: After the page loads, processing runs locally in a Worker without uploading the file. Cancel or clear stops the task.
Illustrative output:
File size & structure constraints
Input must be smaller than 5,000,000 bytes. Limits: 1,000 events, 1,000 properties per component, 50,000 physical lines, 5,000 components, depth 8, 2,000,000 timezone calculation steps, 25,000,000 bytes of combined single-event ICS, and 30 seconds including reading. Fields show 8,000 characters; source pages show 16,000. Downloads are complete. Google and Outlook links add only the selected starting occurrence, without recurrence or invitation semantics. They open an external service only when clicked. ICS retains original recurrence and invitation metadata. Apple uses the downloadable ICS. Native imports and saving to external accounts have not been verified. Embedded VTIMEZONE takes precedence over IANA data. Supports DTSTART/RDATE and YEARLY rules with month/day/weekday/position, interval, count and until selectors. Other embedded rules remain explicitly unresolved. IANA data comes from the browser. Repeated local times use the first occurrence; skipped times use the offset before the jump. Leap seconds use second 59 with a warning and no add link.
iCalendar Events, Time Zones & Recurrence parses structured OpenXML and PDF data locally. Review exported tables or sheets against original files.
Zero-upload document security boundary
File buffers and document assets in iCalendar Events, Time Zones & Recurrence are processed in-memory via local browser APIs with zero file uploads to CZOA servers.
Document schemas & interchange standards
ECMA-376 Office Open XML specifications and ISO 32000 PDF reference standards:
iCalendar Events, Time Zones & Recurrence verification · Audit standards
How to use it
- Choose a local .ics file / Paste ICS source
- Display time zone (IANA) / Process locally
- Event / Download entire calendar ICS
Frequently asked questions
What does the iCalendar Events, Time Zones & Recurrence produce?+
Operational requirements for "What does the iCalendar Events, Time Zones & Recurrence produce?" are verified in local memory during execution of iCalendar Events, Time Zones & Recurrence.
What limits and privacy rules apply?+
Downloads are complete.
Which formats and interoperability limits apply?+
End is exclusive. Without DTEND/DURATION, an all-day event ends the next day; a timed event ends at its start. All-day dates are not shifted between zones. PnD is applied as nominal days before exact hours. For all-day events, this is nominal days × 86,400, not elapsed time across daylight-saving changes.
Can I run a local example?+
Download calendar example /examples/calendar-example.ics