Detailed Comparison of Firefox 15 vs Chrome 21 vs Internet Explorer 10

Firefox new arrival

If you have been an avid follower of our blog, you would know we follow firefox updates quite closely. With every release, we publish the new features and how it fares with other competitors. Off late, the updates haven’t been that interesting in terms of new features, largely due to the nature of rapid release cycle of Firefox. Not so this time, Firefox 15 brings-in some much awaited features, including the much awaited fix for Addon memory leaks, making Firefox the most memory efficient browser out there. We will also compare firefox 15 vs chrome 21 along with Internet Explorer 10 using various benchmarks.

Update : Mozilla is rolling out 15.0.1, a minor update, which fixes the broken Private browsing. The critical bug caused Firefox to record data to browser cache, even in Private browsing which rendered it pointless. Mozilla has been working on the issue ever since its discovery. Firefox will update automatically or alternatively you can download it from the FTP if private browsing is critical for you.

Download: Firefox 15.0.1 [17 MB]

What is Memory leak fix all about?

I can’t emphasize this enough. The web seems to be genuinely excited just because of the addon memory leak fix in Firefox. Finally Firefox seems to get rid of all sorts of memory leaks thanks to the MemShrink project. Blogpost by a Mozilla dev is a good read in itself if you want to jump into the details, but here is the “fix” in a nutshell :

firefox memory fix
Leaky addons usually cause “zombie compartments” or leaks by holding references to a web page even after the page has been closed or navigated away from. This prevents Firefox from clearing the memory consumed by the page’s compartment. So Mozilla basically decided getting away with these references by detecting and cutting them.

This not only results in drastically less memory consumption, when you run Firefox for an extended period with boatload of addons, but also results in much snappy performance. No more long freezes, massive slowdowns and out-of-memory crashes especially on Windows. Just about everything Firefox needed. And I can partially confirm this as I am unable to reproduce the “Not responding” window and the occasional lag on either Windows 7 or Windows 8.


  • Silent Background Updates : A much awaited feature, landing in Firefox 15. Firefox will now update automatically in the background just like Chrome. All I want to exclaim is “Finally!”
  • Inbuilt PDF Reader : A really slick inbuilt PDF reader has been included in this release. Although the support for PDF’s is somewhat preliminary, the reader is performant nonetheless. Firefox js reader

The inbuilt PDF reader requires external PDF plugins for Firefox to be disabled to function. Currently it needs to be enabled in about:config by toggling pdfjs.disabled to false. You can also tinker with few other pdfjs options in about:config to suit the default action.

Firefox js reader enable

  • HTML5 Enhancements : Firefox 15 features numerous HTML5 enhancements as well. Firefox now includes native support for Opus audio codec becoming the first browser to fully support it. Other enhancements include audio and video elements’ support for the played attribute, and source element support for media attribute.

Opus is a completely free (as in free software) audio format. Opus offers better compression than popular codecs like MP3 and AAC. Opus also boasts of dynamically adjustable bitrate, support for interactive as well as pre recorded applications amidst other specs. Mozilla is pushing hard for other browsers to adopt it as common audio format for HTML5.

  • SPDY Protocol v3 support: Firefox now supports SPDY 3. SPDY is basically a open networking Protocol which is developed primarily by Google to support reduce load times . With major platforms like Facebook and WordPress supporting SPDY, this is surely a welcome addition.

Again SPDY v3 support is disabled by default, and it needs to be enabled in about:config by setting network.http.spdy.enabled.v3 to True.

Firefox spdy enable

  • WebGL enhancements: Mozilla has also given plenty of attention towards WebGL . Firefox 15 adds native support for compressed textures in WebGL, and other enhancements to WebGL. Try out the HTML5-Javascript based first person shooter developed by Mozilla to test the new performance enhancements in WebGL.
  • Developer Tools : Finally , Firefox 15 also sports Javascript debugger integrated in developer tools, new layout view added to inspector, and a new responsive design tool which allows devs to switch between desktop and mobile view of sites among other enhancements.

firefox 15 javascript debugger

Firefox 15 vs Chrome 21 vs Internet Explorer 10

This time around we concentrated only on the three major browsers. Internet Explorer 10 from Windows 8 RTM was included along with Chrome 21 and Firefox 15 for our tests. Another major change implemented during this set of benchmarks is adoption of Windows 8 RTM as our test bed instead of Windows 7.

Benchmarks Performed : Fishtank WebGL , Sunspider , Kraken , Google v8  and our own Memory consumption benchmark.


chrome 21 vs ie 10  vs firefox 15 sunspider

Internet Explorer since version 9 has been well known for its performance in sunspider and IE 10 just carries it forward. Firefox though managed to trump Chrome handily in this javascript benchmark.


chrome 21 vs ie 10  vs firefox 15 webgl

Despite the WebGL enhancements made in Firefox 15, I obtained almost the same number as in Firefox 14, though this might be related to the AMD Catalyst driver. Chrome though, had no issues rendering 10 fishes at full 60fps. Internet Explorer on the other hand seems to be targeted towards a parallel universe without the existence of WebGL .


chrome 21 vs ie 10  vs firefox 15 kraken js

Firefox was always trailing behind Chrome by a huge margin in Kraken Benchmark and this time it is again playing the catch up part. Chrome is really the king here.

Memory Consumption

chrome 21 vs ie 10  vs firefox 15 ram

This time again , we performed our routine benchmark of measuring the memory consumption of the browser by opening 10 tabs and calculating the sum of all the processes run by the browser using Process Explorer. Again, Chrome continued its legacy of hogging memory, while Internet Explorer was surprisingly resource conscious. Though, the real star in this area was Firefox. This will just get better because you wont be suffering through any sort of memory leak from addons if you run the browser for long from now on thanks to the new fixes.

Concluding Words

Firefox 15 just feels much more snappy and performing, thanks to the memory leak fixes. Bundle that with handy new additions like inbuilt PDF reader, SPDY v3 support, automatic background updates, and WebGL enhancements, and you have one heck of a powerful browser with tons of addons to make it even more powerful. Try now to feel the difference. DO let us know which one do you prefer Firefox 15 or Chrome 21 or Internet Explorer 10!