Run results for: Split join vs replace

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_4_0 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/135.0.7049.83 Mobile/15E148 Safari/604.1

Browser: Chrome Mobile iOS 135

Operating system: iOS 18.4.0

Device Platform: Mobile

Date tested: one year ago

replace

602.7M/s

split + join

7.4M/s

View exact numbers

Test name	Executions per second
✓ replace	602,737,728 Ops/sec
split + join	7,352,554 Ops/sec

Script Preparation code:

var example = 'AgreementChangeId'

Tests:

split + join
var result = example.split(/(?=[A-Z])/).join(' ');
replace
var result = example.replace(/([A-Z]+)/g, ' $1')