jsPerf.app is an online JavaScript performance benchmark test runner & jsperf.com mirror. It is a complete rewrite in homage to the once excellent jsperf.com now with hopefully a more modern & maintainable codebase.

jsperf.com URLs are mirrored at the same path, e.g:

https://jsperf.com/negative-modulo/2

Can be accessed at:

https://jsperf.app/negative-modulo/2

for vs. while

Benchmark created on October 3, 2011

Preparation HTML

<ul>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
  </li>
  <li class="test">
    Test
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  <li class="test">
    Test
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  <li class="test">
    Test
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  <li class="test">
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  <li class="test">
    Test
  </li>
</ul>
<script>
  var collection = document.querySelectorAll('.test');
  var i = 0;
  var length = collection.length;
  j = length;
</script>

Test runner

Ready to run.

Testing in
Test		Ops/sec
for	`for (i = 0; i < length; i++) { collection[i].className = 'changed'; }`	ready
while	`while (j-- > 0) { collection[j].className = 'changed'; }`	ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.

Revision 1: published on October 3, 2011