@cksharma11/rut-validator/index.js

RUT Validator

exports.validateRut = function (rut) {
  if (!rut) {
    return false;
  }
  /** Remove all non printable characters  */
  rut = rut.replace(/[^\x20-\x7E]+/g, "");
  const [validator, ...number] = rut.replace(/[.-]/g, "").split("").reverse();
  const reNumber = /^\d{8}$/;
  const reValidator = /^[\dkK]{1}$/;
  if (number.length === 7) number.push("0");
  if (!reNumber.test(number.join("")) || !reValidator.test(validator)) {
    return false;
  }
  const multiplier = [2, 3, 4, 5, 6, 7, 2, 3];
  const acc = number.reduce(
    (previousValue, currentValue, currentIndex) =>
      previousValue + +currentValue * multiplier[currentIndex],
    0
  );
  let dv = 11 - (acc % 11);
  dv = dv === 10 ? "K" : `${dv === 11 ? 0 : dv}`;
  const re = new RegExp(`${dv}`, "i");
  return re.test(validator);
};