Run results for: Javascript 'concat()' vs '+' for strings - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.121 Safari/537.36

Browser: Chrome 72

Operating system: Windows

Device Platform: Desktop

Date tested: 5 years ago

Test name	Executions per second
concat()	3556.3 Ops/sec
plus_operator	3482.9 Ops/sec
plus_eq_operator	1408.2 Ops/sec

Website performance monitoring

Script Preparation code:

var string1 = "Hello ";
var string2 = " world!";

Tests:

concat()
for(i = 0; i < 1000; i++) { var message = string1.concat(string2); }
plus_operator
for(i = 0; i < 1000; i++) { var message = string1 + string2; }
plus_eq_operator
for(i = 0; i < 1000; i++) { string1 += string2; }