Run results for: Javascript 'concat()' vs '+' for strings

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.135 Safari/537.36

Browser: Chrome 84

Operating system: Mac OS X 10.15.6

Device Platform: Desktop

Date tested: 4 years ago

Script Preparation code:

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

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

Tests:

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

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

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