The traditional way of inviting friends on Facebook Page or Event is too tedious. Going over friends one by one and clicking on the ‘Invite’ button is only good if you want to invite selective friends but most of us usually prefer to invite all friends to a Facebook page with a single click.
 
Well If that’s your case, then is a simple workaround for this problem. There is an awesome Chrome extension —Facebook Invite All, that lets you do that.
Once installed you will see a tick symbol at the end of address bar which appears only when you are using Facebook on your Google Chrome browser.
This extension only works in a pop-up like a page, therefore to get it work to go to Facebook Page > Build Audience > Invite Friends. Instead of clicking on every invite button next to your friend’s name you can click on the small tick symbol of Facebook Invite All extension and instantly like request would be sent to all your Facebook’s friend.
Check out this small demo video on How to invite all friends to a Facebook page using Facebook Invite All chrome extension.
Update
To control user from sending invites to their friends, Facebook has introduced scroll features on the third-party page. So when you click on Invite your friends to like this Page link on the pages that you don’t own, you get a scroll menu instead of a pop-up box. This update can prevent people from promoting someone else’s page. And apparently, you can use only this chrome extension to invite all friends only on your Facebook page and event.
There is a famous trick of copy pasting the javascript code (as shown below) on URL box or developer console of chrome to send Facebook invites.  Facebook has confirmed that method works even now, but to prevent misuse, the effects are slower.
