JSFiddle - React, Tailwind, and code Playground

by Brondem Brondem

HTML

<form name="formulario">
    <input type="number" name="num"/>
    <output name="out"></output>
</form>

JavaScript

window.onload = function(){
    var form = document.forms.formulario;
    form.oninput = function() {
        form.out.value = form.num.value;
    }
}