age calculator javascript

JavaScript
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript program to calculate age</title>
</head>
<body>

</body>
</html>

function calculate_age(dob) { 
    var diff_ms = Date.now() - dob.getTime();
    var age_dt = new Date(diff_ms); 
  
    return Math.abs(age_dt.getUTCFullYear() - 1970);
}

console.log(calculate_age(new Date(1982, 11, 4)));

console.log(calculate_age(new Date(1962, 1, 1)));
Source

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