JSFiddle - React, Tailwind, and code Playground
HTML
<body>
<form method="post" action="submit.php">
Name: <input type="text" id="name" class="form-control" placeholder="Upisi ime">
</form>
</body>
</html>
JavaScript
$(document).ready(function(){
$('#name').change(function(){
$.ajax({
url: "submit.php",
type: "post",
data: 'name='+ $('#name').val()
});
});
});