This tool will help you to invite multiple FB friends to FB event.
This software is neither created nor endorsed by Facebook.
Privacy notice: This software neither collects nor transmits any personally identifiable information. This software does not track your browsing behaviour. Information necessary for functioning of this software is stored on the devices of end user, our servers do not have access to this information. All information required for functioning of this software is kept between end-user and Facebook servers.
Terms of service: https://www.gethappysoftware.com/tos/
(1) Invite multiple friends to a Facebook event: Allows you to to invite multiple Facebook friends to a Facebook event.