[forwardin]

календарь подключается плагином и привязан к input с классом date_input

<div>
            <form action="#" name="form_1">
                <div class="container">
                    <div class="row">
                        <div class="row-sp" style="width:120px">
                            <button id="select-date">Выбрать дату</button>
		</div>
                        </div>  
                        <div id="news-container clearfix">
		<div class="search-cal col-md-6  col-xs-12">
			<div class="calendar">
  						<p>
    						<input type="text" id="date" name="date" value="" class="date_input row-sp" placeholder="Дата рождения">
    						<input type="text"  name="age" placeholder="Лет" style="width:50px">
  						</p>
                    </div>
			</div>
	</div>                  
                    <div class="row">
                        <div class="row-sp" style="width:80%">
                            <button id="fio">ФИО</button></div>                         
                    </div>
                    <div class="row">
							<div class="row-sp" style="width:350px">&nbsp;
							<textarea cols="50" rows="20" name="textarea_1" style="border: 1px solid #cccccc">							</textarea>
                        </div>
                    </div>
                    <div class="row">
                        <div class="form_1_button-panel">
                            <button id="send">Отправить</button>
                        </div>
                    </div>
                </div>
            </form>

        </div>

<script>
	 var todaydate = new Date();
			var year = new Date();
			var setinput = new Date();
			var dateinput = document.getElementsByTagName('date').value;
			year.setDate(todaydate.getYear()-setinput.getYear());
			console.log(year); 
    console.log(dateinput);
	</script>