OS X Browser Speed Wars: May the Fastest App Win
Posted 09/17/2009 at 4:59pm
| by Michelle Delio
No matter how happy you are with your current Web browser, chances are you’ve wondered if another browser would make your Web wanderings faster, easier, or at least a little more festive. We speculate about that too (probably far too often), so we decided to run some tests, compare features and figure out which browser currently rules the Web.
The Lineup
Browsers are powered by engines which transform a raw mess of HTML, CSS, and JavaScript into a more or less tidy website. Mac browsers typically use the Mozilla Gecko or Webkit engines. Opera uses its own proprietary engine, Presto.
Current releases of Mozilla Gecko-based browsers for the Mac include:
Firefox 3.5.1: Once the geeky alternative, now almost mainstream, known for its customizability
Flock 2.5: A browser for the socially-minded Mac user
Camino 1.6.8: Firefox, basically, but tweaked for Macs
Current Webkit-based browsers include:
Safari 4.0.2: Apple’s very own browser.
Stainless 0.6.5: Cool features for the technically inclined (under development).
Cruz 0.2: For the social networker who likes to multi-task (under development).
If a browser has not yet reached version 1.0, we didn’t include it in our overall benchmark scoring as it could have skewed the results. Early-stage stripped-down betas can appear superfast, and could lack some functions that can skew benchmark-based comparisons.
Testing Methodology
To gauge basic performance levels we used Mozilla's Dromaeo JavaScript testing suite which aggregates a number of tools including Dromaeo, Apple's SunSpider suite and Google's V8. We measured CPU/Memory usage with iStat pro. Streaming video playback was determined by comparing how smoothly the same set of three YouTube videos played in each browser.
We installed freshly-downloaded copies of each browser and tested on a Mac Pro (2.66GHz Quad-Core Intel Xeon with 8GB of SDRAM running OS X 10.5.7) and a MacBook Pro (2.8GHz Intel Core 2 Duo with 8GB SDRAM running OS X 10.5.7). Each browser ran in its default configuration with no third-party plug-ins and a minimum set of bookmarks. That’s the closest we could get to creating a level playing field but there’s a flaw here: over long-term usage, a browser’s performance may slow as information is added to its database, extensions can also bog things down.
Bottom line: Benchmarks are not the Voice of God. There are too many variables that come into play, such as network latency when testing browsers. And while a sluggish but feature-rich application is not a good application, features and functionality matter far more to most of us than whether a browser can load 15 tabs a few fractions of a second faster than another browser.
Test results
General Performance:
Overall, Safari was the fastest of all the browsers we tested, with Camino a hair behind Safari.
Firefox exhibited the slowest startup times of any tested browser, but beats Safari by an average of two seconds in speedy page rendering, primarily due to its new TraceMonkey JavaScript engine.
Opera was a bit faster than Firefox on start-up times but really shone in the tab-tests -- opening up eight, and then 15 tabs faster (but we’re talking percents of seconds here) than the other browsers. Safari was the next fastest on the tab test, with Firefox and Camino neck in neck near the back of the pack.

Flock didn’t score well at all, coming in dead last in all tests but its capabilities not its performance are what makes this browser attractive to some.
Resource Usage
We tested each browser by opening 15 tabs -- nine of them flash-heavy -- and checked CPU and memory usage in iStat pro after 10, 20, and 30 minutes.
Firefox, Safari and Opera did the best on this test; Firefox showed 9% CPU utilization at 30 minutes, Safari and Opera had consumed 11%. Camino was in second-to-last place, with a 13% CPU utilization score. Flock ate up the most resources, spiking to 15% on occasion.
None of the browsers gobbled enough resources to create a performance lags in other applications or the browser.
NEXT: Video Playback, Features Compared and Your Next Browser.