Run results for: new Intl.DateTimeFormat vs cached Intl.DateTimeFormat vs custom

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36

Browser: Chrome 127

Operating system: Windows

Device Platform: Desktop

Date tested: 2 months ago

Test name	Executions per second
new Intl.DateTimeFormat.format()	10662.7 Ops/sec
cached Intl.DateTimeFormat.format()	302187.7 Ops/sec
new Intl.DateTimeFormat.formatToParts	10600.3 Ops/sec
cached Intl.DateTimeFormat.formatToParts()	156026.7 Ops/sec
Custom	1130751.0 Ops/sec

Script Preparation code:

const TWO_DIGIT = '2-digit';

var options = {
      month: TWO_DIGIT,
      year: 'numeric',
      day: TWO_DIGIT,
      hour: TWO_DIGIT,
      hour12: false,
      minute: TWO_DIGIT,
      second: TWO_DIGIT,
    }

var cached = new Intl.DateTimeFormat('en-US', options);

Tests:

new Intl.DateTimeFormat.format()
new Intl.DateTimeFormat('en-US', options).format(new Date());
cached Intl.DateTimeFormat.format()
cached.format(new Date());
new Intl.DateTimeFormat.formatToParts
new Intl.DateTimeFormat('en-US', options).formatToParts(new Date());
cached Intl.DateTimeFormat.formatToParts()
cached.formatToParts(new Date());
Custom
const date = new Date(); const year = date.getFullYear(); const month = (date.getMonth() + 1).toString().padStart(2, '0'); const day = date.getDate().toString().padStart(2, '0'); const hour = date.getHours().toString().padStart(2, '0'); const minute = date.getMinutes().toString().padStart(2, '0'); const second = date.getSeconds().toString().padStart(2, '0'); const millis = date.getMilliseconds(); const t = `${year}-${month}-${day} ${hour}:${minute}:${second},${millis}`; return t

Run results for: new Intl.DateTimeFormat vs cached Intl.DateTimeFormat vs custom

measure the perf impact of caching calls to new Intl.DateTimeFormat

new Intl.DateTimeFormat.format()

cached Intl.DateTimeFormat.format()

new Intl.DateTimeFormat.formatToParts

cached Intl.DateTimeFormat.formatToParts()

Custom