Object.keys vs for in for values

JavaScript performance comparison

Revision 9 of this test case created by juloo

Preparation code

<script>

</script>
<script>
Benchmark.prototype.setup = function() {
    var keys = Object.keys;
    var hasOwnProperty = Object.prototype.hasOwnProperty;
   
    var obj = {
      'prop1': 'value1',
      'prop2': 'value2',
      'prop3': 'value3',
      'prop4': 'value4',
      'prop5': 'value5',
      'prop6': 'value6',
      'prop7': 'value7',
      'prop8': 'value8',
      'prop9': 'value9',
      'prop10': 'value10'
    };
};
</script>

Test runner

Warning! For accurate results, please disable Firebug before running the tests. (Why?)

Java applet disabled.

Testing in unknown unknown
Test Ops/sec
Object.keys
var props = keys(obj),
  index = -1,
  length = keys.length,
  values = [];

while (++index < length) {
  values.push(obj[props[index]]);
}
pending…
for-in w/ hasOwnProperty
var values = [];
for (var prop in obj) {
  if (hasOwnProperty.call(obj, prop)) {
    values.push(obj[prop]);
  }
}
pending…
Object.keys / for loop
var values = [];

for (var props = keys(obj), i = 0; i < keys.length; i++) {
  values.push(obj[props[i]]);
}
pending…

Compare results of other browsers

Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

0 comments

Add a comment