Answers for "html textarea rows auto"

textarea scale to content

<textarea rows="10" style="font-size: 2vw; width:100%;"></textarea>

html textarea auto height to amount of text

$('textarea').each(function () {
  this.setAttribute('style', 'height:' + (this.scrollHeight) + 'px;overflow-y:hidden;');
}).on('input', function () {
  this.style.height = 'auto';
  this.style.height = (this.scrollHeight) + 'px';
});