Some JS to ensure that a user doesn't enter a value that is less than or greater than the min/max values allowed for a number input.

min-max-enforcement.js

$('#element').change(function() {
  var $this = $(this);

  if ($this.val() > $this.attr('max')) {
    $this.val($this.attr('max'));
  } else if ($this.val() < $this.attr('min')) {
    $this.val($this.attr('min'));
  }
});