Run results for: Regex vs split/join

Run details:

User agent: Mozilla/5.0 (Android 8.1.0; Mobile; rv:67.0) Gecko/67.0 Firefox/67.0

Browser: Firefox Mobile 67

Operating system: Android 8.1.0

Device Platform: Mobile

Date tested: 5 years ago

Test name	Executions per second
Regex	23457.0 Ops/sec
Split and Join	867936.1 Ops/sec

Script Preparation code:

var str = 'Abcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxyAbcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxy';

Tests:

Regex
str.replace(/./g, "$&Z");
Split and Join
str.split('').join('Z') + 'Z';

Run results for: Regex vs split/join

Regex

Split and Join