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

+ vs string.concat (v4)

Revision 4 of this benchmark created on March 29, 2011

Preparation HTML

<script>
  var str = '',
      hello = 'Hello ',
      world = 'World ';
</script>

Test runner

Ready to run.

Testing in
Test		Ops/sec
add	`str = hello + world;`	ready
concat	`str = hello.concat(world);`	ready

Revisions

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

Revision 1: published on March 28, 2011
Revision 3: published on March 28, 2011
Revision 4: published on March 29, 2011
Revision 5: published by Craig on March 29, 2011