WebKit launches JetStream2 browser benchmark

Martin Brinkmann
Mar 28, 2019

WebKit launched JetStream 2, a new benchmark suite to measure the performance of JavaScript and WebAssembly operations in web browsers recently.

Browser benchmarks were a huge thing back when Google Chrome launched. Google used them to demonstrate how much faster Chrome's JavaScript performance was when compared to Internet Explorer or Firefox, the two main browsers back in the day.

One of the effects was that browser makers started to optimize and improve the performance of JavaScript; this resulted in benchmarks becoming less important as speed improved in browsers.

JetStream 2

JetStream 2 tests JavaScript and WebAssembly performance of web browsers as well as the performance of other functions such as Web Workers. Just hit the start button on the JetStream 2 benchmark website to test the browser.

JetStream 2 also includes a new set of benchmarks that measure the performance of Web Assembly, Web Workers, Promises, async iteration, unicode regular expressions, and JavaScript parsing.

The browser benchmark runs 64 tests, some of which come from other benchmarks such as JetStream, SunSpider, or Octane. The development team describes each of the tests that JetStream 2 runs on this page.

The team ran the benchmark on a MacBook Pro to compare the results of Safari, Chrome and Firefox. Safari took the crown in the test followed by Chrome (about 8% slower) and Firefox (about 68% slower).

I decided to ran the test on a Windows machine. While I could not run Safari on Windows, I ran the benchmark in recent stable versions of Chrome, Firefox and Microsoft Edge.

Chrome managed to get a score of about 105, Firefox a score of 78 in the benchmark. Firefox Nightly got an Infinity score instead which suggests that something broke while the test was running. The test did not complete in Microsoft Edge and I had to stop it as it would not even finish the first test of the benchmark suite.

Closing Words

The new benchmark suggests that Mozilla has some work to do to close the performance gap according to the benchmark. Benchmarks don't necessarily relate to real-world performance though.

Now You: Did you run the benchmark? How did browsers installed on your device perform?

WebKit launches JetStream2 browser benchmark
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WebKit launches JetStream2 browser benchmark
WebKit launched JetStream 2, a new benchmark suite to measure the performance of JavaScript and WebAssembly operations in web browsers recently.
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  1. John IL said on April 26, 2019 at 9:22 pm

    Also concur that Edge can’t seem to even begin the test let alone finish it. Not sure what to make of that but I also ran Edge Chromium against Chrome and got 80.97 and 84.151 respectively. So Microsoft doing OK with Edge Chromium development.

  2. ilev said on April 17, 2019 at 11:17 am

    Chrome Version 74.0.3729.75 (Official Build) beta (64-bit) : 128.149 (20 extension)

  3. AlexLSM said on March 28, 2019 at 5:07 pm

    My tests, all browsers are updated to the latest version:

    Opera: ~76k (my main browser with a lot of extensions)
    Chromium: ~76k (slightly more than Opera) (no extensions)
    Chrome: ~78k (only uBlock origin)
    Firefox: ~56k (only uBlock origin)

    As can be seen, Chromium browsers are pretty much all the same and all comes to personal preferences.
    Firefox is lagging behind significantly and it is obvious, you don’t need a test to see that.

    1. Anonymous said on March 29, 2019 at 2:23 am

      Hmm, let’s see why…

      Developer(s): Apple Inc., Adobe Systems, ***GOOGLE***

      Want to bet it is optimized for Safari & Chrome?

      1. AlexLSM said on March 29, 2019 at 4:14 pm

        Could be. But in my everyday use Firefox is noticeably slower than the rest of browsers, sometimes it is not even close.
        Average user doesn’t care (or even know) that sites are optimized for Chrome(Chromium) and/or Safari but not for Firefox. Average user wants Firefox to be as fast and currently it is not.

        I’ve been using Firefox for more than 10 years but now it is not nowhere near as good as it was which is a shame.

  4. Tom Hawack said on March 28, 2019 at 3:03 pm

    I surf (only on the Web, unfortunately) as I jog : more as a ride, a walk than as a race.
    I surf as I’d drive from NY to LA (or Paris to Moscow) : with the comfort of a camping-car rather than with the speed of a dragster.

    I don’t have the slightest interest for speed (unless of course the reference is a snail) and even less for comparison benchmarks : as long as a browser fits my needs and preferences (that means tweaks and dedicated extensions) and privacy/security expectations, it’s all good & go for me.

    Especially that the deltas nowadays are in terms of milliseconds, hardly perceptible, why would I start fantasizing on pure speed? Why races, why this obsession of being first, of winning, what does that bring, fame? I don’t give a damn for fame.

  5. Bobby Phoenix said on March 28, 2019 at 1:52 pm

    Hmm. I guess the scores are close enough that I can’t really tell differences in performance between Firefox and Chrome. I switch between both a lot, and both perform the same for me. I use Firefox more for the engine as I find for me it renders pages better especially fonts. Firefox also handles certain sites I use for work a lot better, and has a much better PDF reader built in. Not to mention much better privacy features. I guess it’s like running a car on a Dyno. Sure one car can get better performance results than the other on a standard test, but that doesn’t mean it’s the better car overall.

  6. John IL said on March 28, 2019 at 12:31 pm

    Jetstream has always been a pretty good benchmark, the version 2 appears to again to raise the bar for measuring success of browser performance. Not surprised that Firefox was far behind, in my experience personally I have not found Firefox to be that good. I try it, but I keep coming back to Chrome or some clone built on Chromium. Its obviously a much better web engine then Gecko even with Quantum improvements. Probably a reason why Microsoft decided to implement Chromium and V8 into its Edge browser. Sadly the people at Mozilla these days seem clueless about what’s important.

  7. yossarian said on March 28, 2019 at 8:16 am

    I’m on Linux Mint 19.1 and running two browsers. Main browser is
    Vivaldi and score is 82.082
    Firefox and score is 52.428
    and used rarely.

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