Welcome folks today in this blog post we will be building a stylish font calculator in html5 css3 and javascript. All the full source code of the application is shown below.

Get Started

In order to get started you need to make an index.html file and copy paste the following code

index.html

<div class='container'>
  <div id='calculator'>

    <!-- TITLE -->

    <div id='title' class='text-center'>
      <h5><b>ELECTRONIC CALCULATOR</b></h5>
    </div>

    <!-- ENTRY BOX -->

    <div id='entrybox' class='text-right'>
      <div id='entry'>
        <p id='answer'>0</p>
      </div>
      <div id='history'>
        <p>0</p>
      </div>
    </div>

    <!-- BUTTONS -->

    <div id='buttons'>

      <button class='red' value='ac'>AC</button>
      <button class='red' value='ce'>CE</button>
      <button value='/'>÷</button>
      <button value='*'>x</button>

      <button value='7'>7</button>
      <button value='8'>8</button>
      <button value='9'>9</button>
      <button value='-'>-</button>

      <button value='4'>4</button>
      <button value='5'>5</button>
      <button value='6'>6</button>
      <button value='+'>+</button>


      <button value='1'>1</button>
      <button value='2'>2</button>
      <button value='3'>3</button>
      <button class='invisible'>N</button>

      <button id='zeroButton' value='0'>0</button>
      <button value='.'>.</button>
      <button id='equalButton' value='='>=</button>

    </div>
    <!-- end buttons -->
    <div id='tester'></div>
  </div>
  <!-- end calculator -->
</div>
<!-- end container -->

<footer id="footer" class="text-center">
  <div class="container">
    Designed & Coded by
    <a href="https://www.linkedin.com/in/justin-woodward-891772118" target="_blank">
        Justin Woodward</a>
  </div>
</footer>

And now make an style.css file and copy paste the following code

style.css

body {
  font-family: 'Orbitron', sans-serif;
  background-color: #818181;
}

#calculator {
  height: 410px;
  width: 300px;
  margin-top: 10%;
  margin-left: auto;
  margin-right: auto;
  background-color: #dfd8d0;
  border: 2px solid #908b85;
  border-radius: 20px;
  box-shadow: 7px 10px 34px 1px rgba(0, 0, 0, 0.68), inset -1px -6px 12px 0.1px #89847e;
}

#title {
  padding-top: 10px;
  padding-bottom: 10px;
}

#entrybox {
  width: 85%;
  height: 65px;
  margin-left: auto;
  margin-right: auto;
  border: 2px solid #b4b39d;
  border-radius: 6px;
  background-color: #c3c2ab;
}

#entry {
  margin-right: 10px;
  font-size: 35px;
}

#buttons {
  font-size: 16px;
  font-weight: bold;
  color: #fff;
  position: absolute;
  display: inline-block;
  width: 280px;
  height: auto;
  margin-top: 15px;
  margin-left: 15px;
}

button {
  border-radius: 8px;
  border: none;
  background-color: #3a3a3a;
  margin: 0 4px 10px 8px;
  height: 40px;
  width: 50px;
  box-shadow: 0px 3px 0px 0px #222121, inset -1px -3px 10px 1px #515151;
}

button:active {
  transform: translate(0px, 3px);
  box-shadow: none;
}

.row {
  margin-top: 20px
}

#topAdjust {
  margin-top: -52px;
}

#equalButton {
  position: absolute;
  margin-left: 12px;
  margin-top: -50px;
  height: 90px;
}

#zeroButton {
  width: 117px;
}

.red {
  font-size: 14px;
  background-color: #a72d45;
  box-shadow: 0px 3px 0px 0px #671c2a;
}

#footer {
  font-family: 'Josefin Sans', sans-serif;
  position: relative;
  font-size: 16px;
  font-weight: normal;
  margin-top: 40px;
  width: 100%;
  height: 40px;
}

button,
button:hover,
button:active,
button:visited {
  text-decoration: none !important;
  outline: none !important;
}

a,
a:hover,
a:active,
a:visited {
  color: #922031;
  text-decoration: none !important;
  outline: none !important;
}

#history {
  /*transform: translate(-13px, -17px);*/
  position: relative;
  height: 10px;
  bottom: 17px;
  margin-right: 14px;
  color: #8b8b7b;
  font-size: 12px;
}

And now make an script.js file and copy paste the following code

script.js

// final draft
$(document).ready(function() {

  var entry = '';
  var ans = '';
  var current = '';
  var log = '';
  var decimal = true;
  var reset = '';

  // round function if answer includes a decimal
  function round(val) {
    val = val.toString().split('');
    if (val.indexOf('.') !== -1) {
      var valTest = val.slice(val.indexOf('.') + 1, val.length);
      val = val.slice(0, val.indexOf('.') + 1);
      var i = 0;
      while (valTest[i] < 1) {
        i++
      }
      valTest = valTest.join('').slice(0, i + 2);
      if (valTest[valTest.length-1] === '0') {
        valTest = valTest.slice(0, -1);
      }
      return val.join('') + valTest;
    } else {
      return val.join('');
    }
  }

  $('button').click(function() {

    entry = $(this).attr("value");
    console.log('entry: ' + entry);

    //reset for log after answer to equation.
    if (reset) {
      if (entry === '/' || entry === '*' || entry === '-' || entry === '+') {
        log = ans;
      } else {
        ans = '';
      }
    }
    reset = false;

    // All clear or Clear Entry
    if (entry === 'ac' || entry === 'ce' && current === 'noChange') {
      ans = '';
      current = '';
      entry = '';
      log = '';
      $('#history').html('0');
      $('#answer').html('0');
      decimal = true;
    } else if (entry === 'ce') {
      $('#history').html(log.slice(0, -current.length));
      log = log.slice(0, -current.length);
      ans = ans.slice(0, -current.length);
      current = ans;
      if (log.length === 0 || log === ' ') {
        $('#history').html('0');
      }
      $('#answer').html('0');
      entry = '';
      decimal = true;
    }

    // prevents more than one deciminal in a number
    if (entry === '.' || entry === '0.') {
      if (!decimal) {
        entry = '';
      }
    }

    // prevents improper use of first digit
    if (ans.length === 0 && isNaN(entry) && entry !== '.' || ans.length === 0 && entry === '0') {
      entry = '';
      ans = '';
    }

    // prevents extra operators
    if (current !== 'noChange') {
      if (current === '' && isNaN(entry) && entry !== '.' || isNaN(current) && isNaN(entry) && entry !== '.') {
        entry = '';
      }
    }

    // digit combining
    while (Number(entry) || entry === '0' || current === '.') {

      if (isNaN(current) && entry === '0' && current !== '.') {
        entry = '';
      } else if (isNaN(current) && Number(entry) && current !== '.') {
        current = '';
      }
      if (entry === '.') {
        decimal = false;
      }
      if (current === '0.' && isNaN(entry)) {
        entry = '';
      } else {
        if (current[current.length - 1] === '.') {
          current = current.concat(entry);
        } else {
          current += entry;
        }
        ans += entry;
        $('#answer').html(current);
        log += entry;
        $('#history').html(log);
        entry = '';
      }
    }

    // Operation list

    if (entry === '.') {
      if (current === '' || isNaN(current[current.length - 1])) {
        current = '0.';
        ans += entry;
        $('#answer').html('0.');
        log += current;
        $('#history').html(log);

      } else {
        current = current.concat('.');
        ans = ans.concat('.');
        log = ans;
        $('#history').html(ans);
        $('#answer').html(current);
      }
      entry = '';
      decimal = false;

    } else if (entry === '/') {
      current = '/';
      ans = round(eval(ans)) + current;
      log += current;
      $('#history').html(log);
      $('#answer').html('/');
      entry = '';
      decimal = true;

    } else if (entry === '*') {
      current = '*';
      ans = round(eval(ans)) + current;
      log += 'x';
      $('#history').html(log);
      $('#answer').html('x');
      entry = '';
      decimal = true;

    } else if (entry === '-') {
      current = '-';
      ans = round(eval(ans)) + current;
      log += current;
      $('#history').html(log);
      $('#answer').html('-');
      entry = '';
      decimal = true;

    } else if (entry === '+') {
      current = '+';
      ans = round(eval(ans)) + current;
      log += current;
      $('#history').html(log);
      $('#answer').html('+');
      entry = '';
      decimal = true;

    } else if (entry === '=') {
      if (current[current.length - 1] === '.') {
        entry = '';
      } else {
        current = eval(ans).toString();
        $('#answer').html(round(eval(ans)));
        ans = round(eval(ans));
        log += entry + ans;
        $('#history').html(log);
        log = ans;
        entry = '';
        reset = true;
        decimal = true;
      }
      current = 'noChange';
    }
    entry = '';

    if (reset) {
      log = '';
    }

    // max digits on screen
    if ($('#entry').children().text().length > 8 || $('#history').text().length > 22) {
      $('#answer').html('0');
      $('#history').html('Digit Limit Met');
      current = '';
      ans = '';
      log = '';
      decimal = true;
    }

    console.log('decimal: ' + decimal);
    console.log('current: ' + current);
    console.log('answer: ' + ans);
    console.log($('#history').text().length);
  });
}); // end doc ready function

And now if you open index.html file inside the browser you will see the below output