JSFiddle - React, Tailwind, and code Playground

HTML

<input id="from" type="text" class="datepicker" />
<input id="to" type="text" class="datepicker" />
<input id="submit" value="Send" type="submit" />

JavaScript

//  2013-10-21T00:00:00

Number.prototype.padLeft = function(base,chr){
    var  len = (String(base || 10).length - String(this).length)+1;
    return len > 0 ? new Array(len).join(chr || '0')+this : this;
}

function parseDate(d) {
    return [d.getDate().padLeft(), (d.getMonth()+1).padLeft(), d.getFullYear()].join('/')+'T'+
           [d.getHours().padLeft(), d.getMinutes().padLeft(), d.getSeconds().padLeft()].join(':');
}

$(function () {
    $(".datepicker").datepicker();

    $("#submit").click(function () {
        var from = $('#from').datepicker('getDate');
        var to   = $('#to').datepicker('getDate');
        
        console.log( "xxxx/?from=" + parseDate(from) + "&to=" + parseDate(to) );
    
        $.getJSON("xxxx/?from=" + parseDate(from) + "&to=" + parseDate(to));
    });
});