Run results for: Intl.NumberFormat vs toLocalString vs string split & replace & join

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser: Chrome 119

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
toLocaleString	35874.8 Ops/sec
Intl.NumberFormat	34325.1 Ops/sec
string split & reduce	1444198.0 Ops/sec

Script Preparation code:

function pricize (n) {
  const parts = n.toString().split('.')

  parts[0] = parts[0].replace(/\B(?=(\d{3})+(?!\d))/g, ',')

  return parts.join('.')
}

var target = 123456789.123456789
var options = { maximumFractionDigits: 20 }

Tests:

toLocaleString
var a = target.toLocaleString('en-US', options);
Intl.NumberFormat
var a = new Intl.NumberFormat('en-US', options).format(target)
string split & reduce
var a = pricize(target)

Run results for: Intl.NumberFormat vs toLocalString vs string split & replace & join

toLocaleString

Intl.NumberFormat

string split & reduce