Opera claims on its own website that its latest beta  version, Opera 10.50b, is the fastest browser the world has seen so far. This statement is based on test results from different browser benchmarks published on the official Opera blog.

As Google Chrome has been the fastest browser for a while and the alpha version of Opera 10.50 caught up quite well with Chrome’s performance but didn’t beat it yet, I decided to check the benchmark results given in the blog post by Opera. I ran all the benchmarks with the same settings as Opera did and also tested all four browsers. The only difference is that I used Chrome 5 (alpha) instead of Chrome 4 which is justified since Opera is also using non-stable builds of their browser. I summed up all the benchmark results in a diagram quite similar to the one used by Opera in order to make comparison easier:

The diagram published by Opera looks like this:

As you can see, the latest version of Opera really beats Chrome in Peacekeeper and Dromaeo, but Chrome is far ahead in both Sunspider and V8. I ran all the benchmarks several times to verify my test results and they are perfectly valid, but still differ from the ones published by Opera somehow. Now one has to ask why there is such a big difference regarding Sunspider and whether Opera faked its scores or the latest version of Chrome really improved in this sector.

All in all, it’s quite clear that Opera is really trying to beat all other browsers when concerning JavaScript performance and manages to catch up with Chrome. It will be interesting to see whether the final version of Opera 10.50 will beat Chrome in all tests or not.

In contrast to Opera, I want my  benchmark results to be rock-solid and not to be challenged, so I took screenshots of each result and also created an Excel file that contains all results and the calculations made to create the diagram. You can download the screenshots and the Excel file to check my results.

EDIT:
I spoke to the Opera development team and after some tests, we came to the conclusion that the missing support for SSE4.1 and 4.2 is what makes my Phenom slower than the Core 2 Duo in the Sunspider benchmark.