From our experience with the APIs of the big players in the event listing market
(Upcoming, Zvents, Eventful, TicketMaster, etc.), it is evident there is no standard
format being used to exchange event information behind the scenes.

Each API arbitrarily assigns its own naming scheme, date formats and data structure. We’ve had to pick up the slack at Localist by developing customized parsers to retrieve and standardize the information for each service.

We’d like to start a discussion with interested people in the industry about creating a standardized data interchange format. We’ve already created a preliminary standard, dubbed ELF (Event Listing Format), that can easily work with all existing services, along with an explanation of how it complements hCalendar. You can check out some example RAW XMLs too.

We know this community is filled with ridiculously smart people — some who may be interested in taking part in this discussion. If you, or anyone you know would like to be involved, shoot an e-mail to myke at

UPDATE: A wiki page has been created to bring some organization to everyone’s ideas. There’s also a discussion happening in #elf on Freenode.