Run results for: foreach vs for vs for (length var) vs for..in vs for..of - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:83.0) Gecko/20100101 Firefox/83.0

Browser: Firefox 83

Operating system: Windows

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
forEach	372402.4 Ops/sec
for	1911613.4 Ops/sec
for with length var	1510894.5 Ops/sec
for..in	27352.3 Ops/sec
for..of	112208.8 Ops/sec

Script Preparation code:

var array = new Array(1000);
for(i=0; i<array.length; i++){
  array[i] = Math.random();
}

Tests:

forEach
array.forEach(function(i) { i; })
for
for (var i = 0; i < array.length; i++) { array[i]; }
for with length var
for (var i = 0, n = array.length; i < n; i++) { array[i]; }
for..in
for (var i in array) { array[i]; }
for..of
for (var i of array) { i; }

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