Most standard calendar exchange data format

Question

I have a system (php/MySQL) with a scheduler application.

I'm about to create a service which would allow users to read their calendar from outlook, google, sunbird, ...

I'm wondering what is the most standard format today for exchanging calendar data.

Is it ical ?

Answer 1

Yes, iCalendar - most recently documented in RFC 5545 - is probably your best bet. It won't be much fun, however... and expect to find various quirks in different implementations. If you can possibly stick to some simple subset of the standard, that's likely to help you immensely.