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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <div class="container">
      <div class="panel panel-default">
    <div class="row">
      <h3 class="panel-title">Hex Converter</h3>
  <div class="panel-body">
    Hexidecimal use the following characters:<br>
    <div class="form-group">
    <input id="myHex" class="form-control" type="input" />
    <input id="submit" class="btn btn-default" type="button" value="Calculate" onclick="calculate()" />
    <input id="reset" class="btn btn-default" type="button" value="Reset" onclick="reset()" />
        </div><hr />
      <div id="answer" class="answer"></div>
    <div id="answer2" class="answer"></div>

  background: #4fc3f7

  background: #ffffff;
  width: 450px;
  height: 370px;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);

  font-size: 1.5em

  background: #65499c;
  color: #ffffff;
  padding-left: 20px;

  background: #65499c;
  color: #ffffff

  font-size: 1em;
  margin-left: 1px;

Hex calculator - created this to help me understand how to convert hex to decimal 
I ran into a problem with JS precision can working with very large numbers. Imported Big.js library to get expected results. 
Used this formula: 7DE = (7 * 16^2) + (13 * 16^1) + (14 * 16^0)
Hexadecimal: 123456789ABCDEF A = 10, B = 11, C = 12; D = 13; E = 14; F = 15
value * 16 to the power of the value's place x*16^y
Used https://www.binaryhexconverter.com/hex-to-decimal-converter to check calculations.

Added binary conversion function called "toBin()" 
var node = document.getElementById("answer");
var node2 = document.getElementById("answer2");
function calculate() {
  var inputValue = document.getElementById("myHex").value;
  //var node = document.getElementById("answer")
  inputValue = inputValue.toUpperCase();
  var array = inputValue.split("");
  //reverse array to ensure values match place number found in "index" array
  array = array.reverse();
  //letters in "array" replaced with corresponding number
  var arrayNew = [];
  var ans = [];
  var index = [];
  var calc;
  for (var i = 0; i < array.length; i++) {
    //switch changes hex letters to numbers
    switch (array[i]) {
      case "A":
        array[i] = "10";
      case "B":
        array[i] = "11";
      case "C":
        array[i] = "12";
      case "D":
        array[i] = "13";
      case "E":
        array[i] = "14";
      case "F":
        array[i] = "15";

    arrayNew.push(parseInt(array[i], 10));
    var t = new Big(16);
    var z = t.pow(index[i]);
    //z = z.toString();
    calc = new Big(arrayNew[i]);
    var s = calc.times(z);
  function getSum(total, num) {
    var x = new Big(total);
    var y = x.add(num);
    return y;
  var answer = ans.reduce(getSum);

  var remove = node.childNodes[0];
  if (!remove) {
  } else {
  if (answer > 9223372036854775807) {
      document.createTextNode("Must be smaller than 7FFFFFFFFFFFFFFF")
  } else {
    node.appendChild(document.createTextNode("Decimal: " + answer));
    node2.appendChild(document.createTextNode("Binary: " + toBin(answer)));

function reset() {
  document.getElementById("myHex").value = "";

function toBin(num) {
  var divBy2 = [];
  var quo = [];
  var bits = [];
  var bit;
  var quotient;
  var remain;
  divBy2.push(num); //insert the initial number
  quotient = Math.floor(num / 2);
  bit = num % 2;
  do {
    quotient = Math.floor(quotient / 2);
  } while (quotient > 0);
  divBy2.pop(); //removes 0 that is not needed from end of array

  for (var i = 1; i < divBy2.length; i++) {
    bit = divBy2[i] % 2;
  return bits.reverse().join("");

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