Number Format Explorer

const formatter = new Intl.NumberFormat("en-US", {
    "notation": "standard",
    "signDisplay": "auto",
    "useGrouping": true,
    "minimumFractionDigits": 0,
    "maximumFractionDigits": 3,
    "style": "decimal"
  });

console.log(formatter.format(1234567.89));