World Clock & Meeting Planner
Date & time Local only
ICS Calendar Editor & Validator
Local RFC 5545 workspaceCreate, edit, merge, deduplicate, validate and export ICS calendars with recurrence and conflict analysis.
Understand and repair an ICS calendar
Create or open iCalendar files, edit events and recurrence, merge duplicates, inspect conflicts and export a privacy-reviewed copy.
Calendars remain local
ICS parsing, editing, recurrence expansion and downloads happen in this browser. The tool does not subscribe to or sync remote calendars.
How to use it
- 01
Open or create a calendar
Parse a local ICS file with ICAL.js, create a blank calendar, or use the recurring and conflicting example.
- 02
Edit and analyze events
Use month and agenda views to edit details and recurrence, then review conflicts and explainable diagnostics.
- 03
Merge and export
Merge another ICS, deduplicate UID and start pairs, and export ICS, redacted ICS, CSV or JSON.
Frequently asked questions
Does this subscribe to an online calendar?
No. It edits imported files locally and does not connect to CalDAV, Google Calendar or remote subscription URLs.
How are time zones handled?
Original TZID evidence is shown, while edited date-times are exported as explicit UTC to avoid silently treating local wall time as UTC. Complex VTIMEZONE rules still deserve review in the target calendar app.
How far are recurring conflicts checked?
The conflict view expands a bounded twelve-month window beginning at the displayed month, with an occurrence cap for browser safety.
What does the redacted export remove?
It replaces UIDs and omits description, location, organizer and attendees while preserving timing, recurrence and summary for schedule review.
Related tools
Keep working with other focused browser utilities.