JSFiddle - React, Tailwind, and code Playground
by jfriend00
JavaScript
var prevTime = new Date(2011,1,1,0,0); // Jan 1, 2011
var thisTime = new Date(); // now
var diff = thisTime.getTime() - prevTime.getTime(); // now - jan 1
alert(diff / (1000*60*60*24)); // positive number of days