JSFiddle - React, Tailwind, and code Playground
JavaScript
var dob = 1525219200;
var now = Date.now();
var age = new Date();
age = (dob - now).toUTCString()
document.write("dob: " + dob + "<br/>");
document.write("now: " + now + "<br/>");
document.write("age: " + age + "<br/>");