JSFiddle - React, Tailwind, and code Playground

by shreejana dangol

JavaScript

var n = "1234567890123456";
document.write(n.replace(/(\d{4})(\d{4})(\d{4})(\d{4})/, '$1-$2-$3-$4'));

var str = "100, 1000 or 100?";
    var patt1 = /\d{4}/g;
    var result = str.match(patt1);