Run results for: new Date(date) vs new Date(normalizeToLocalDate(date)) 2

Run details:

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Mobile Safari/537.36

Browser: Chrome Mobile 127

Operating system: Android

Device Platform: Mobile

Date tested: one year ago

new Date(dateOnlyISO)

2.1M/s

new Date(dateTimeISO)

1.6M/s

new Date(normalizeToLocalDate(dateTimeISO))

1.5M/s

new Date(normalizeToLocalDate(dateOnlyISO))

986K/s

View exact numbers

Test name	Executions per second
✓ new Date(dateOnlyISO)	2,105,176 Ops/sec
new Date(dateTimeISO)	1,617,069 Ops/sec
new Date(normalizeToLocalDate(dateTimeISO))	1,475,082 Ops/sec
new Date(normalizeToLocalDate(dateOnlyISO))	986,165 Ops/sec

Script Preparation code:

var dateTimeISO = '2024-08-21T17:00:00.000Z'
var dateOnlyISO = '2024-08-21'

var normalizeToLocalDate = (date) => ` ${date}`

Tests:

new Date(dateTimeISO)
new Date(dateTimeISO)
new Date(normalizeToLocalDate(dateTimeISO))
new Date(normalizeToLocalDate(dateTimeISO))
new Date(dateOnlyISO)
new Date(dateOnlyISO)
new Date(normalizeToLocalDate(dateOnlyISO))
new Date(normalizeToLocalDate(dateOnlyISO))