date

var birthDate = document.getElementById("id");

        var format = "mm/dd/yyyy";
        var match = new RegExp(format
            .replace(/(\w+)\W(\w+)\W(\w+)/, "^\\s*($1)\\W*($2)?\\W*($3)?([0-9]*).*")
            .replace(/m|d|y/g, "\\d"));
        var replace = "$1/$2/$3$4"
            .replace(/\//g, format.match(/\W/));

        function format(target)
        {
            target.value = target.value
                .replace(/(^|\W)(?=\d\W)/g, "$10")   // padding
                .replace(match, replace)             // fields
                .replace(/(\W)+/g, "$1");            // remove repeats
        }

        birthDate.addEventListener( 'keyup', function(e){
            if(!e.ctrlKey && !e.metaKey && (e.keyCode == 32 || e.keyCode > 46))
                format(e.target)
        });