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)));
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