Calendar
5 tools, including CSV to ICS, ICS to CSV, ICS to JSON and ICS viewer. All free, with no account and nothing to install.
CSV to ICSTurn a spreadsheet of dates into a calendar file any app can subscribe to.ICS to CSVTurn a calendar file into a spreadsheet of events, with real dates instead of ICS stamps.ICS to JSONExport calendar events as JSON, with each ICS timestamp converted to ISO-8601.ICS viewerOpen a calendar invitation or export and read its events before importing anything.Merge ICS filesCombine several calendar files into one, keeping every event.