TIL: The navigation timing API includes the type of the current navigation

Paul Calvano wrote an excellent article diving into back/forward caches in which he goes into RUM metrics gathered with mPulse.

I learned that it is possible to access user navigation behavior info in JavaScript. You can see if your users navigated, reloaded or traversed the browser history. The Navigation Timing spec and particularly the included Navigation Type hold this information in performance.navigation.type. performance.navigation.type returns an enum value.

Navigation Event	Enum value	Info
navigate	0	lick click, entering of a URL, form submission, ...
reload	1	reload click or location.reload()
back_forward	2	back/forward click or calling history.back()/history.forward()
prerender	3	navigation initiated by a prerender hint

You can use performance.navigation.type to analyze how your site and its reasources load depending on different user behavior. For example, if you want to learn how many people hit the reload button on your pages and want to do some analysis, a few lines of JavaScript can help here:

if (performance.navigation.type === 1) {
  // gather metrics after a reload and
  // tell your monitoring service about it!
}

If you want to see the Navigation Timing API in action, I published a CodeSandbox to play around with it.

Have fun! 👋