Número de formato JavaScript com K M

const nFormatter = (num, digits) => {
  const lookup = [
    { value: 1, symbol: "" },
    { value: 1e3, symbol: "K" },
    { value: 1e6, symbol: "M" },
    { value: 1e9, symbol: "G" },
    { value: 1e12, symbol: "T" },
    { value: 1e15, symbol: "P" },
    { value: 1e18, symbol: "E" }
  ]
  
  const rx = /\.0+$|(\.[0-9]*[1-9])0+$/
  const item = lookup.slice().reverse().find((item) => {
    return num >= item.value
  })
  return item ? (num / item.value).toFixed(digits).replace(rx, "$1") + item.symbol : "0"
}

nFormatter(2500) // => 2.5K
nFormatter(1000000) // => 1M
Lioruby