Fastmail This document defines how to convert calendaring information between the JSCalendar and iCalendar data formats. It considers every JSCalendar and iCalendar element registered at IANA at the time of publication. It defines conversion rules for all elements that are common to both formats, as well as how convert arbitrary or unknown JSCalendar and iCalendar elements. This document updates RFC 5545 ("iCalendar") and jscalendarbis ("JSCalendar") by defining new properties and parameters for JSCalendar and iCalendar conversion.