@wojtekmaj/react-hooks/dist/useScrollTopPercent.js

A collection of React Hooks.

import useScrollTop from './useScrollTop.js';
import useWindowHeight from './useWindowHeight.js';
export default function useScrollTopPercent() {
    const scrollTop = useScrollTop();
    const windowHeight = useWindowHeight();
    if (scrollTop === null || windowHeight === null) {
        return null;
    }
    const { scrollHeight } = document.documentElement;
    if (scrollHeight === 0) {
        return 0;
    }
    return scrollTop / Math.max(0, scrollHeight - windowHeight);
}