Run results for: for vs forEach

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:54.0) Gecko/20100101 Firefox/54.0

Browser: Firefox 54

Operating system: Windows

Device Platform: Other

Date tested: 7 years ago

Test name	Executions per second
for cached length	322.6 Ops/sec
forEach	649.9 Ops/sec
forEach cached function	654.0 Ops/sec

Script Preparation code:

  var i,
      value,
      length,
      values = [],
      sum = 0,
      context = values;
  
  
  for (i = 0; i < 10000; i++) {
      values[i] = Math.random();
  }
  
  function add(val) {
      sum += val;
  }

Tests:

for cached length
length = values.length; for (i = 0; i < length; i++) { sum += values[i]; }
forEach
values.forEach( function(val) { sum += val; } );
forEach cached function
values.forEach( add );

Run results for: for vs forEach

for cached length

forEach

forEach cached function