Fast Firefox Faceoff: Nightly vs. Pale Moon vs. Waterfox

Today's Best Tech Deals

Picked by PCWorld's Editors

Top Deals On Great Products

Picked by Techconnect's Editors

Although computers running the 64-bit version of Windows 7 have become more common, there aren't many Windows-compatible browsers compiled to run on 64-bit processors. (The exception for now has been Internet Explorer 9.)

This includes Firefox. However, "official" is the key word since Mozilla has developed alpha versions of Firefox that support Windows 64-bit, and there are two other browsers built by independent developers based on Firefox's open-source code.

10 must-have Firefox extensions

We took a look at three Firefox variants made for 64-bit processor computers running a 64-bit version of Windows, giving each a series of tests to rate its speed and performance. (One caveat, Firefox Nightly releases a new version almost every day, so your results may vary.)

There are a lot of sites that purport to test the speed of a web browser (i.e. running it through a battery of tests to rate how quickly it can render images, run CSS, execute JavaScript, etc.). Because these three browsers are based on Firefox code, we tested them on Mozilla's own benchmark site, Kraken. You can read details at its official wiki. We ran the Kraken test three times -- twice in a row, the third after rebooting the computer -- and picked the lowest number result. (Under Kraken, the lower number is the better rating, representing the fastest performance.)

We also timed how long it took for each browser to cold-start after Windows was rebooted, and then checked its memory usage with just one blank tab open.

Tech argument: browser wars

We then timed how long it took to load and fully render the main page of our own site,, with the browser's history and cache cleared. (We did this three separate times.) We checked the memory usage of each with one tab open on

None of the browsers had any extensions installed when we tested them. In the case of the second browser, Pale Moon comes with a built-in toolbar extension. It could not be uninstalled, but it could be disabled which we did prior to testing.

The system we tested these 64-bit browsers on was a Dell Inspiron 1440 notebook, running a 2.20GHz Pentium Dual-Core T4400, with 4GB RAM. The OS was Windows 7 Home Premium, 64-bit version.

If you decide to install any of these 64-bit browsers, we suggest you still keep the 32-bit version of Firefox on your system. Most of your favorite Firefox extensions should work under the 64-bit browser, but many media plug-ins which normally run on Firefox 32-bit may not work with these 64-bit counterparts. So you may want to install the 64-bit version of Flash. Otherwise, some Flash sites and media may not run when you use one of these 64-bit web browsers.

Firefox Nightly (Version 12.0a1, dated 1/28/2012)

Official website

Mozilla puts out a new 64-bit version of Firefox for Windows 64-bit almost every day...or night, as it were. These fall under the codename Nightly, which is Mozilla's designation for frequently released Firefox alphas. As of this writing, the version number of the Firefox code base which Nightly uses is 12.0. (By comparison, the official stable release of Firefox is 9.0.1.) Nightly browsers may include experimental features, but skirt the edge of stability since they are not fully tested.

Adding confusion to this, Mozilla has another alpha category for Firefox, called Aurora, which releases under a more frequent schedule than Firefox Beta, but less than Nightly. Aurora is at Version 11, but it does not have a 64-bit version that runs on Windows 64-bit. Mozilla also does not provide a 64-bit version of Firefox Beta for Windows 64-bit. (Firefox Beta is presently at Version 10.0.)

Because it's updated almost daily, expect Nightly's stability to be volatile -- one day it could work great for you, but the next day after you update it with the latest release, it may not (until maybe the next day after you update it again...).

Here are the performance results:

Kraken benchmark result: 5844.7 milliseconds

Time to load from cold start: 4.5 seconds

Memory usage with one blank tab open: 48MB

Time to open 5.8 seconds

Memory usage with one tab open on 96MB

Pale Moon (Version 9.1)

Official website

Pale Moon comes from a developer who has been creating builds of Firefox and other Mozilla programs -- Thunderbird and SeaMonkey -- optimized for specific processors ever since Firefox was at Version 1.5. His 64-bit Firefox for Windows 64-bit is based on the Firefox 9.0.1 code base, which is the stable version officially released by Mozilla for Firefox 32-bit.

A benefit of Pale Moon is that it keeps to itself -- it functions separately, keeping any add-ons you install on it apart from any other version of Firefox that you may have on your computer, and not loading the add-ons and user profiles associated with the other Firefox.

There's a caveat to the memory usage results below: When Pale Moon runs, it also runs one or more separate processes in the background of Windows called ""Plugin Container for Palemoon". These processes ranged in number of one to three, and sizes from 8M to 25MB, when we tested the browser.

Here are the performance results:

Kraken: 6187.6 milliseconds

Time to load from cold start: 5.5 seconds

Memory usage with one blank tab open: 76MB

Time to open 5.8 seconds

Memory usage with one tab open on 106MB

Waterfox (Version 9.0)

Official website

The developers of Waterfox claim their 64-bit spin on Firefox is the fastest. It's built on the Version 9.0 stable release of Firefox. As of Jan. 7, Waterfox became the de facto "unofficial official" 64-bit version of Firefox for Windows 64-bit when it became a project accepted by Mozilla.

After installing it, we got a system error when trying to run Waterfox for the first time: "The program can't start because MSVCR100.dll is missing..." The FAQs on the Waterfox site lists the solution, which requires installing Visual C++ 2010 Redistributable Package (x64). This seems a bit odd since neither Nightly nor Pale Moon required this. Once we plugged in this package, Waterfox then loaded without a problem.

Performance results:

Kraken: 6058.4 milliseconds

Time to load from cold start: 4.4 seconds

Memory usage with one blank tab open: 55MB

Time to open 5.2 seconds

Memory usage with one tab open on 107MB


Pale Moon rated the slowest in the Kraken test and took the longest (by just a second more over Nightly and Waterfox) to load from a cold start. It appears to use the most memory over the other two 64-bit browsers, and the mysterious background processes that it runs probably need to be considered and added to its overall memory-use tally.

The latest Nightly we tested slightly beat Waterfox on Kraken, but the latter browser loaded the fastest from cold start (though by a millisecond, which is negligible, of course). Nightly uses less memory when it has one blank tab open, and less when displaying an open page, compared with Waterfox where the opposite situation appears to occur.

Of course, all of these stats are negligible and subject to change (especially with Nightly being updated so often). Practically speaking, it looks like a toss-up between Firefox Nightly and Waterfox -- that is, using a 64-bit browser with experimental, in-development code over a more reliable, stable base.

So Waterfox is the closest to an official 64-bit version of Firefox for Windows 64-bit that's based on the browser's latest stable release (9.0) -- until Mozilla rolls out its own version, if ever.

Wen is a freelance writer. He can be reached at

Read more about software in Network World's Software section.

This story, "Fast Firefox Faceoff: Nightly vs. Pale Moon vs. Waterfox" was originally published by Network World.

Note: When you purchase something after clicking links in our articles, we may earn a small commission. Read our affiliate link policy for more details.
Shop Tech Products at Amazon