Simple UTF8 string bytes counter

bytesCounter.js

/**
 * Simple UTF8 String bytes counter
 * @author Tomas Aparicio 
 * @license MIT
 * @param {String} str String to count
 * @return {Number} Bytes
 * @method bytesCounter
 */
function bytesCounter(str){
    var code, i, bytes = 0;
    for (i=0;i<str.length;i+=1) {
      code = str.charCodeAt(i);
      if (code < 129) {
        bytes += 1;
      } else if (code < 2049) { 
        bytes += 2;
      } else {
        bytes += 3;
      }
    }
    return bytes;
}
  
// test
console.log(bytesCounter('@ sámplE $tRinG| ª&%_.^·~)(= ?¿[-]'));
console.log(bytesCounter('华语/華語 普通话'));