settimeout.js

const start = Date.now();

const today = new Date().toISOString();
console.log({today});

console.log({start})

setTimeOut(function(){
  const end = Date.now();
  console.log({setTimeOutTook: (end - start) / 1000 });
}, 3000);

setInterval(function(){
  const end = Date.now();
  console.log({setIntervalTook: (end - start) / 1000 });
}, 1500);