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We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

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HTML Settings

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.

              <input id="cc" type="text" name="creditcard"
  placeholder="XXXX XXXX XXXX XXXX" style="width: 150px">
              $('#cc').on('input propertychange', function() {
  var node = $('#cc')[0]; // vanilla javascript element
  var cursor = node.selectionStart; // store cursor position
  var lastValue = $('#cc').val(); // get value before formatting
  var formattedValue = formatCardNumber(lastValue);
  $('#cc').val(formattedValue); // set value to formatted
  // keep the cursor at the end on addition of spaces
  if(cursor === lastValue.length) {
    cursor = formattedValue.length;
    // decrement cursor when backspacing
    // i.e. "4444 |" => backspace => "4444|"
    if($('#cc').attr('data-lastvalue') && $('#cc').attr('data-lastvalue').charAt(cursor - 1) == " ") {

  if (lastValue !== formattedValue) {
    // increment cursor when inserting character before a space
    // i.e. "1234| 6" => "5" typed => "1234 5|6"
    if(lastValue.charAt(cursor) == " " && formattedValue.charAt(cursor - 1) == " ") {
  // set cursor position
  node.selectionStart = cursor;
  node.selectionEnd = cursor;
  // store last value
  $('#cc').attr('data-lastvalue', formattedValue);

function formatCardNumber(value) {
  // remove all non digit characters
  var value = value.replace(/\D/g, '');
  var formattedValue;
  var maxLength;
  // american express, 15 digits
  if ((/^3[47]\d{0,13}$/).test(value)) {
    formattedValue = value.replace(/(\d{4})/, '$1 ').replace(/(\d{4}) (\d{6})/, '$1 $2 ');
    maxLength = 17;
  } else if((/^3(?:0[0-5]|[68]\d)\d{0,11}$/).test(value)) { // diner's club, 14 digits
    formattedValue = value.replace(/(\d{4})/, '$1 ').replace(/(\d{4}) (\d{6})/, '$1 $2 ');
    maxLength = 16;
  } else if ((/^\d{0,16}$/).test(value)) { // regular cc number, 16 digits
    formattedValue = value.replace(/(\d{4})/, '$1 ').replace(/(\d{4}) (\d{4})/, '$1 $2 ').replace(/(\d{4}) (\d{4}) (\d{4})/, '$1 $2 $3 ');
    maxLength = 19;
  $('#cc').attr('maxlength', maxLength);
  return formattedValue;
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