Binary search in javascript

Binary-search.js

const binSearch = (list, val) => {
  let min = 0, max = list.length - 1, index, guess;
  
  while(min <= max) {
    index = Math.ceil((min + max) / 2, 10);
    guess = list[index];
     if (guess === val) {
        return index;
     } else if (guess > val) {
      max = index - 1;
     } else {
      min = index + 1;
     }
  }
  return -1;
}