Browsers JavaScript performance test

Browser is today one of the most important aplications – very often we don’t have to use other, specific aplications, we need only browser to open not only pages, but also complex internet services and apps, email clients, remote desktops, stream, play games or use social media. Most of these services are based on JavaScript, so performance in this area is very, very important for overall browser performance. There are many browsers, but we have only limited browsers engines now. I decided to made a small test and compare popular browsers JavaScript performance. Results are not surprised me, but have some interesting conclusions.

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I am not a software tester, I don’t have full, complex environment to make big tests, so I decided to use only one, but very good (in my opinion) – Speedometer 2.0 from It simulates real internet application, so it’s good example. I made all tests on MacBook Pro 15 2018 with Intel i7-8750H CPU, 16 GB RAM and 256 GB SSD drive. Computer was connected to 5K display, so it used Radeon Pro 555X GPU all the time. I also use latest stable MacOS Mojave (10.14.6, complication 18G95). I choose several browsers for this test – popular, but not only these. In some cases like Vivaldi, I used only stable version, because it’s not so popular to test also latest development, nightly build.

I plan to repeat such test every now and then, so, if you have any suggestions, what can I do to make it better, just write a comment. I’m open to any ideas – but remember, I’m not professional tester, have limited time and capabilities, so prefer to make this as simple, as possible. Maybe separate page with only results and updates will be the best option? I’m not sure.


There are result, sorted by score (points in Speedometer) – higher is better:

Safari Technology Preview (13.1, TP91)114
Vivaldi Stable (2.7.1628.33)111
Safari Stable (12.1.2)110
Brave Stable (0.68.132)109
Chrome Canary ( 78.0.3904.5)105
Opera Stable (63.0.3368.75)105
Opera Developer (65.0.3425.0)104
Chrome Stable (76.0.3809.132)95
Firefox Stable (69.0)86
Firefox Developer Edition (70.0b4)83
Firefox Nightly (71.0a1)80


First thing – the winner is latest development version of Safari. I’m not surprised, because Safair JavaScript performance was always good. It’s very nice, but does not encourage me to switch, go back to Safari. It’s a good browser, but last time Apple made a lot of stupid decisions like change extensions API and now developers must write special apps only for MacOS to provide Safari extensions. All other browers offers much simpler methods using HTML5, only Apple solutions is different. Think different… Stupid. Also Stable version of Safari is very fast, and if it’s enough for you, it’s very good choice to daily usage.

Second place is Vivaldi and it was suprise. Ok, Vivaldi is Chromium-based browser, and all these browser are good in JS performance but… Vivaldi is also a “browser monster”, with a lot, a lot of great… or sometimes completely useless options. It’s good to know, that these all additional options doesn’t touch JS performance. It’s very nice. Next places are Brave – this browser has build-in adblocker / tracking scripts blocker. Very fast without issues. Then Opera, both versions with very similar results. Great browser, only one based on Chromium, which can use integrated GPU instead of using Radeon GPU on MacOS in all websites.

Last three places is Mozilla Firefox in different versions. Mozilla made a lot of changes and good changes, but still must improve JS engine. They said, that newer versions (70+) should be faster, but this simple test can confirm this. Maybe because of some debug options enabled in default in Developer or Nightly versions? I’m not sure. In daily usage these differences are not visible for user, but may be visible for overall performance and also battery life: slower JS = longer page loading = worst battery life. They must do something with that as soon, as possible. Latest stable versions improve battery life on Mac, but it’s still not great: the same as Chrome, but still much worse than Safari.