diff --git a/files/en-us/web/api/element/scrollheight/index.md b/files/en-us/web/api/element/scrollheight/index.md
index 5b6920da6e0b16d..1981092127f1505 100644
--- a/files/en-us/web/api/element/scrollheight/index.md
+++ b/files/en-us/web/api/element/scrollheight/index.md
@@ -175,7 +175,8 @@ const veryImportantRead = document.getElementById("very-important-read");
 // Check if user has scrolled the element to the bottom
 function isRead(element) {
   return (
-    element.scrollHeight - Math.round(element.scrollTop) <= element.clientHeight
+    Math.abs(element.scrollHeight - element.clientHeight - element.scrollTop) <=
+    1
   );
 }