javascript での年齢計算のサンプルを備忘録

// 2つの日付から年齢を計算
function getAge(d1, d2){
    d2 = d2 || new Date();
    var diff = d2.getTime() - d1.getTime();
    return Math.floor(diff / (1000 * 60 * 60 * 24 * 365.25));
}
// タグに年齢を表示
function setAge(birthday) {
    if (birthday == '') {
        $("#age").html("");
    } else {
        var bday = new Date(birthday);
        var age = getAge(bday);
        $("#age").html("年齢: " + age + " 歳");
    }
}

参考：https://stackoverflow.com/questions/4076321/javascript-age-calculation