Run details:
Mozilla/5.0 (Macintosh; Intel Mac OS X 11_2_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.90 Safari/537.36
Chrome 89
Mac OS X 11.2.3
Desktop
4 years ago
Test name Executions per second
Array constructor - 10 items 4982989.5 Ops/sec
Array literal - 10 items 24939660.0 Ops/sec
Array literal (assign by index) - 10 items 21006244.0 Ops/sec
Array literal (explicit length) - 10 items 6188071.0 Ops/sec
Tests:
  • Array constructor - 10 items

    x
     
    var n = 10;
    var arr = new Array(n);
    for (var i = 0; i < n; i++) {
      arr[i] = i;
    }
  • Array literal - 10 items

     
    var n = 10;
    var arr = [];
    for (var i = 0; i < n; i++) {
      arr.push(i);
    } 
  • Array literal (assign by index) - 10 items

     
    var n = 10;
    var arr = [];
    for (var i = 0; i < n; i++) {
      arr[i] = i;
    } 
  • Array literal (explicit length) - 10 items

     
    var n = 10;
    var arr = [];
    arr.length = n;
    for (var i = 0; i < n; i++) {
      arr[i] = i;
    }