javascript max characters string function

const getMaxLetter = (str) => {
  let max = 0;
  let maxChar = '';
  str.split('').forEach((char) => {
    if (str.split(char).length > max) {
      max = str.split(char).length - 1;
      maxChar = char;
    }
  });
  return `The max letter is : ${maxChar} and the max number of times it is seen is: ${max} times`;
};function maxChar(str) {
  let charCountObj = {};
  let maxChar = "";
  let maxCount = 0;

  //  Fill out CharCountObj
  //  Updates new MaxCount

  for (let i = 0; i < str.length; i++) {
    const char = str[i];

    charCountObj[char] = charCountObj[char] + 1 || 1;

    if (charCountObj[char] > maxCount) {
      maxChar = char;
      maxCount = charCountObj[char];
    }
  }

  return maxChar;
}