JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" class="qty1" value="" />
    <input type="text" class="qty1" value="" />
    <input type="text" class="qty1" value="" />
    <input type="text" class="qty1" value="" />
    <input type="text" class="qty1" value="" />
    <input type="text" class="qty1" value="" />

    <input type="text" class="total" value="" />

CSS

input {display: block;}
input.total {margin-top: 30px;}

JavaScript

$(document).on("change", ".qty1", function() {
    var sum = 0;
    $(".qty1").each(function(){
        sum += +$(this).val();
    });
    $(".total").val(sum);
});