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Property Name



This property defines one or more free or busy time intervals.

Value Type


Property Parameters

IANA, non-standard, and free/busy time type property parameters can be specified on this property.


The property can be specified in a "VFREEBUSY" calendar component.


These time periods can be specified as either a start and end DATE-TIME or a start DATE-TIME and DURATION. The date and time MUST be a UTC time format.

"FREEBUSY" properties within the "VFREEBUSY" calendar component SHOULD be sorted in ascending order, based on start time and then end time, with the earliest periods first.

The "FREEBUSY" property can specify more than one value, separated by the COMMA character. In such cases, the "FREEBUSY" property values MUST all be of the same "FBTYPE" property parameter type (e.g., all values of a particular "FBTYPE" listed together in a single property).

Format Definition

This property is defined by the following notation:

 freebusy   = "FREEBUSY" fbparam ":" fbvalue CRLF

 fbparam    = *(
            ; The following is OPTIONAL,
            ; but MUST NOT occur more than once.
            (";" fbtypeparam) /
            ; The following is OPTIONAL,
            ; and MAY occur more than once.
            (";" other-param)

 fbvalue    = period *("," period)
 ;Time value MUST be in the UTC time format.


The following are some examples of this property




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