Simple SI unit conversion

simple-si-unit-conversion.js

const SI =  {
        UNITS: ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'],
        BASE: 1024
 }
function calculateFileDisplayLength(bytes){
    const units = SI.UNITS
    const base = SI.BASE
    let magnitude = 0;
    let accuracy = 0
    let unit = units[magnitude]
    let decimal = bytes
    if (bytes === 0) {
      return '0'
    }

    if(_.isNil(bytes)){
      return ' '
    }

    if (bytes > base) {
      magnitude = Math.floor(Math.log(bytes) / Math.log(base))
      if (magnitude < units.length) {
        unit = units[magnitude]
        decimal = (bytes / Math.pow(base, magnitude))
        accuracy = Math.ceil(decimal % 1)
      }
    }

    return `${decimal.toFixed(accuracy)} ${unit}`
  }
}