我有点晚了，但我发现这是计算出生日期的最简单的方法。

希望这能有所帮助。

function init() { writeYears("myage", 0, Age()); } function Age() { var birthday = new Date(1997, 02, 01), //Year, month-1 , day. today = new Date(), one_year = 1000 * 60 * 60 * 24 * 365; return Math.floor((today.getTime() - birthday.getTime()) / one_year); } function writeYears(id, current, maximum) { document.getElementById(id).innerHTML = current; if (current < maximum) { setTimeout(function() { writeYears(id, ++current, maximum); }, Math.sin(current / maximum) * 200); } } init() <span id="myage"></span>

看这个例子，你从这里得到完整的年、月、日信息

function getAge(dateString) {
    var today = new Date();
    var birthDate = new Date(dateString);
    var age = today.getFullYear() - birthDate.getFullYear();
    var m = today.getMonth() - birthDate.getMonth();
    var da = today.getDate() - birthDate.getDate();
    if (m < 0 || (m === 0 && today.getDate() < birthDate.getDate())) {
        age--;
    }
    if(m<0){
        m +=12;
    }
    if(da<0){
        da +=30;
    }
    return age+" years "+ Math.abs(m) + "months"+ Math.abs(da) + " days";
}
alert('age: ' + getAge("1987/08/31"));    
[http://jsfiddle.net/tapos00/2g70ue5y/][1]

function age()
{
    var birthdate = $j('#birthDate').val(); // in   "mm/dd/yyyy" format
    var senddate = $j('#expireDate').val(); // in   "mm/dd/yyyy" format
    var x = birthdate.split("/");    
    var y = senddate.split("/");
    var bdays = x[1];
    var bmonths = x[0];
    var byear = x[2];
    //alert(bdays);
    var sdays = y[1];
    var smonths = y[0];
    var syear = y[2];
    //alert(sdays);

    if(sdays < bdays)
    {
        sdays = parseInt(sdays) + 30;
        smonths = parseInt(smonths) - 1;
        //alert(sdays);
        var fdays = sdays - bdays;
        //alert(fdays);
    }
    else{
        var fdays = sdays - bdays;
    }

    if(smonths < bmonths)
    {
        smonths = parseInt(smonths) + 12;
        syear = syear - 1;
        var fmonths = smonths - bmonths;
    }
    else
    {
        var fmonths = smonths - bmonths;
    }

    var fyear = syear - byear;
    document.getElementById('patientAge').value = fyear+' years '+fmonths+' months '+fdays+' days';
}

你可以在你的表格中使用这个年龄限制

function dobvalidator(birthDateString){
    strs = birthDateString.split("-");
    var dd = strs[0];
    var mm = strs[1];
    var yy = strs[2];

    var d = new Date();
    var ds = d.getDate();
    var ms = d.getMonth();
    var ys = d.getFullYear();
    var accepted_age = 18;

    var days = ((accepted_age * 12) * 30) + (ms * 30) + ds;
    var age = (((ys - yy) * 12) * 30) + ((12 - mm) * 30) + parseInt(30 - dd);

    if((days - age) <= '0'){
        console.log((days - age));
        alert('You are at-least ' + accepted_age);
    }else{
        console.log((days - age));
        alert('You are not at-least ' + accepted_age);
    }
}

momentjs:

/* The difference, in years, between NOW and 2012-05-07 */
moment().diff(moment('20120507', 'YYYYMMDD'), 'years')

这个问题已经超过10年了，没有人回答过提示，他们已经有了YYYYMMDD格式的出生日期?

如果你有一个YYYYMMDD格式的过去日期和当前日期，你可以像这样快速计算它们之间的年数:

var pastDate = '20101030';
var currentDate = '20210622';
var years = Math.floor( ( currentDate - pastDate ) * 0.0001 );
// 10 (10.9592)

你可以得到当前日期格式为YYYYMMDD，如下所示:

var now = new Date();

var currentDate = [
    now.getFullYear(),
    ('0' + (now.getMonth() + 1) ).slice(-2),
    ('0' + now.getDate() ).slice(-2),
].join('');