unload — 2 Technical Articles

Oct 20, 2025 · Frontend Development

How to Detect When Users Leave a Web Page and Send Reliable Data

This article explains various browser scenarios that indicate a user has left a page, compares the Page Visibility API, beforeunload/unload events, navigator.sendBeacon, and pagehide/pageshow handling, and provides practical code examples and recommendations for reliable detection and data reporting.

beforeunloadfrontendpage-visibility

0 likes · 10 min read

How to Detect When Users Leave a Web Page and Send Reliable Data

JavaScript

Jul 19, 2025 · Frontend Development

How to Reliably Send Data When Users Close a Page: sendBeacon vs fetch keepalive

This article explains why traditional fetch or XMLHttpRequest calls often fail during page unload, and demonstrates two modern browser APIs—navigator.sendBeacon and fetch with keepalive:true—that reliably transmit analytics or draft data without blocking the user experience.

JavaScriptWeb APIfetch keepalive

0 likes · 7 min read