Run results for: DateTimeFormat vs toLocaleString2

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser: Chrome 131

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
DateTimeFormat single	745970.0 Ops/sec
toLocaleString single	27341.8 Ops/sec
DateTimeFormat 100	7513.1 Ops/sec
toLocaleString 100	270.5 Ops/sec
DateTimeFormat 10000	74.6 Ops/sec
toLocaleString 10000	2.5 Ops/sec

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

/*your preparation JavaScript code goes here */
var options = {
  year: 'numeric', month: 'numeric', day: 'numeric',
  hour: 'numeric', minute: 'numeric', second: 'numeric',
  hour12: false,
  fractionalSecondDigits: 3,
}
var formatter = new Intl.DateTimeFormat('de-DE', options)

Tests:

DateTimeFormat single
formatter.format(new Date())
toLocaleString single
new Date().toLocaleString('de-DE', options)
DateTimeFormat 100
[...Array(100)].forEach((_, i) => formatter.format(new Date()))
toLocaleString 100
[...Array(100)].forEach((_, i) => new Date().toLocaleString('de-DE', options))
DateTimeFormat 10000
[...Array(10000)].forEach((_, i) => formatter.format(new Date()))
toLocaleString 10000
[...Array(10000)].forEach((_, i) => new Date().toLocaleString('de-DE', options))

Run results for: DateTimeFormat vs toLocaleString2

DateTimeFormat single

toLocaleString single

DateTimeFormat 100

toLocaleString 100

DateTimeFormat 10000

toLocaleString 10000