This section contains iCalendar related news, including news about this site and iCalendar news from around the globe.  Do you have an interesting iCalendar related story? We would love to hear about it.  Send us a message using our contact us page.

New Validator Release Provides New Checks, Including an RFC 7986 Check

The iCalendar validator at recently celebrated its 3rd anniversery.  Active development continues with the recent release of version 1.11. This version includes several new checks, including the validator's first check against RFC 7986.

RFC 7986 was released in October 2016 as an addendum, not a replacement, for the iCalendar specification 5545. However, one of the few areas of RFC 7986 where it replaces the original specification is with the UID property. The original specification suggests the use of host names, IP addresses and domain names in the creation of the UID string. This suggestion was removed in RFC 7986 and rewritten to exclude any identifying strings due to privacy issues and instead use a random string. The validator checks for domain names simply by checking for a major TLD at the end of the UID (i.e., ".com") and generates a warning. This is not an exhaustive check but it does signal to the user to refer to the new recommendation.

Other checks have been added for the DTSTART and DTEND values. There is now a check to verify the DTEND date does not occur before the DTSTART date, and another check to verify the DTSTART and DTEND date types are the same. DTSTART and DTEND must both be either dates or date-time values and mixing of types will now generate an error.

New RRULE Tool Now Available

A new tool for generating RRULE strings is now available on under the "RRULE Tool" menu option. With the tool, you can generate RRULE strings for events with repeating days, weeks, months and years.

Validator Moves From Beta to Production

After more than 2 years of development and feedback from users, the iCalendar validator here at has moved from beta to production status with the release of version 1.8. In addition to the status change, the latest version also adds a few enhancements made from suggestions by the user community (a version history is available here).

As the year comes to a close, we are happy to see usage of the validator more than double from the previous year. For the new year, we will continue to strive to have the best iCalendar validator available on the web with continued support and development, and as always, welcome feedback from users.

RFC 7986 Specification Added

A new iCalendar specification was officially released in October 2016.  RFC 7986, entitled "New Properties for iCalendar", adds to the original iCalendar RFC by defining new properties to support conferencing systems and to the main VCALENDAR object including a calendar name, description and refresh interval. This RFC has been added to the specifications section at this site and the iCalendar history has been updated to reflect the new RFC.

November Update Brings JSON Support to Validator

The November update for's iCalendar validator adds JSON support. JSON is a data format that is typically used by JSON supported web applications to provide data processing when the HTML formatted data is not sufficient. Third party debugging tools are one example. JSON support is available when validating by URL, where two permalinks are now displayed: one for the HTML formatted results of the validation and one for the JSON formatted results.  The JSON permalink is simply the HTML permalink with the string "&json=1" appended to it.

JSON support adds another unique feature of our validator. We strive to have the best iCalendar validator available today on the web with continued support and development of enhancements like this one.

Spammers Target Apple iCal Users

Spammers are always looking for new ways to target their message that will bypass (at least temporarily) standard spam tracking software.  A recent target was Apple's iCal application through the use of iCalendar invites.

Read more: Spammers Target Apple iCal Users

New iCalendar News Section

We have begun a new section here at iCalendar News. This section will contain iCalendar related news articles, including industry news and news relating to our own site, . If you find an interesting iCalendar news story, we would love to hear about it. Send us a comment in the contact us section of this web site.