BM Calcutor

Calculate your BMI

by kidino

HTML

<label>Height (m)</label>
<input id="height" type="text" />
<label>Weight (kg)</label>
<input id="weight" type="text" />
<button id="calc">Calculate</button>
<div id="result"></div>

CSS

input, label, button { float: left; }
label, button {clear: left;}
#result { border: 1px solid #f00; clear: both; padding: 5px; }

JavaScript

document.getElementById("calc").onclick=function(){
    var height = parseFloat(document.getElementById('height').value);
    var weight = parseFloat(document.getElementById('weight').value);
    var bmi = weight / (height * height);

    var category = '';
    if (bmi < 15) { category = 'Very severely underweight'; }
    if (bmi >= 15) { category = 'Severely underweight'; }
    if (bmi >= 16) { category = 'Underweight'; }
    if (bmi >= 18.5) { category = 'Normal'; }
    if (bmi >= 25) { category = 'Overweight'; }
    if (bmi >= 30) { category = 'Obese Class I'; }
    if (bmi >= 35) { category = 'Obese Class II'; }
    if (bmi >= 40) { category = 'Obese Class III'; }
    document.getElementById('result').innerHTML = bmi.toFixed(2) +" : " + category;
};