Run results for: Compare spread operator and concat in arrays

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:69.0) Gecko/20100101 Firefox/69.0

Browser: Firefox 69

Operating system: Mac OS X 10.13

Device Platform: Desktop

Date tested: 5 years ago

Test name	Executions per second
Using the spread operator	24033.0 Ops/sec
Using Array.prototype.concat	52762.0 Ops/sec

Script Preparation code:

var array1 = [];
var array2 = [];

for (let i = 0; i < 1000; i++) {
  array1[i] = Math.floor(Math.random() * 100);
  array2[i] = Math.floor(Math.random() * 100);
}

​x
 
var array1 = [];var array2 = [];​for (let i = 0; i < 1000; i++) {  array1[i] = Math.floor(Math.random() * 100);  array2[i] = Math.floor(Math.random() * 100);}

Tests:

Using the spread operator
const array3 = [...array1, ...array2];
const array3 = [...array1, ...array2];
Using Array.prototype.concat
const array3 = array1.concat(array2);
const array3 = array1.concat(array2);

Run results for: Compare spread operator and concat in arrays

This benchmark is to compare the cost of using the spread operator

Using the spread operator

Using Array.prototype.concat