The Beacon API makes it easy for web developers to send small amounts of data, such as analytics or diagnostics data, back to the server asynchronously while the current page is unloading. In this article, we’ll look at some of the problems the Beacon API solves, and show you how to use the API.
Without the Beacon API, sending data back to your server when the user navigates away from a page can be trickier than it seems. You don’t want to delay the next page from loading, as this would harm the user’s experience of your site. Yet you don’t want to loose valuable information that could help improve your site: sending the data too early might mean you loose valuable information that you could have captured if you’d waited a fraction longer.