Run results for: Split Join vs Basic string replace

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36

Browser: Chrome 71

Operating system: Windows

Device Platform: Desktop

Date tested: 5 years ago

Test name	Executions per second
Replace (SIMPLE)	1554354.0 Ops/sec
Split and Join	85885.1 Ops/sec
Replace (REGEX)	54985.5 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:

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

Run results for: Split Join vs Basic string replace

Replace (SIMPLE)

Split and Join

Replace (REGEX)