Bounce rate measures the proportion of sessions in which a user lands on a page and leaves without interacting with any other page on the site. A high bounce rate can indicate that a page’s content doesn’t match visitor expectations, the page loads too slowly, or the user experience is poor. However, context matters — a high bounce rate on a contact page may simply mean the user found the phone number they needed. In GA4, bounce rate is defined as the inverse of engagement rate.