yarn add scroll-percentage
import { calculateScrollPercentage } from 'scroll-percentage'
Provide the scrollable element as parameter -
calculateScrollPercentage(scrollabaleElement)
Like -
document.querySelector('.scorllable-elem').addEventListener('scroll',e => {
let scrollPercentage = calculateScrollPercentage(e.target)
console.log('scroll percentage', scrollPercentage)
})
If the scrollable element is window, then a second parameter is necessary.
The second parameter - height of the element, window
is scrolling by -
calculateScrollPercentage(e.target, document.querySelector(someElement).clientHeight)