diff --git a/source/js/utils.js b/source/js/utils.js
index 9b363069eb..4305f5e32d 100644
--- a/source/js/utils.js
+++ b/source/js/utils.js
@@ -135,20 +135,18 @@ NexT.utils = {
     var readingProgressBar = document.querySelector('.reading-progress-bar');
     // For init back to top in sidebar if page was scrolled after page refresh.
     window.addEventListener('scroll', () => {
-      var scrollPercent;
       if (backToTop || readingProgressBar) {
         var docHeight = document.querySelector('.container').offsetHeight;
         var winHeight = window.innerHeight;
         var contentVisibilityHeight = docHeight > winHeight ? docHeight - winHeight : document.body.scrollHeight - winHeight;
-        var scrollPercentRounded = Math.round(100 * window.scrollY / contentVisibilityHeight);
-        scrollPercent = Math.min(scrollPercentRounded, 100) + '%';
-      }
-      if (backToTop) {
-        backToTop.classList.toggle('back-to-top-on', window.scrollY > THRESHOLD);
-        backToTop.querySelector('span').innerText = scrollPercent;
-      }
-      if (readingProgressBar) {
-        readingProgressBar.style.width = scrollPercent;
+        var scrollPercent = Math.min(100 * window.scrollY / contentVisibilityHeight, 100);
+        if (backToTop) {
+          backToTop.classList.toggle('back-to-top-on', window.scrollY > THRESHOLD);
+          backToTop.querySelector('span').innerText = Math.round(scrollPercent) + '%';
+        }
+        if (readingProgressBar) {
+          readingProgressBar.style.width = scrollPercent.toFixed(2) + '%';
+        }
       }
     });