Chrome 13, Firefox 6, Safari 5.1, and Mac OS X Lion (10.7) have all emerged since our last Web Browser Grand Prix. Today, we test the latest browsers on both major platforms. How do the Mac-based browsers stack up against their Windows 7 counterparts?

We have a whole lot of exciting geekery planned today. But first, let's get everyone up to speed. There have been a handful of developments in the world of Web browsing since Web Browser Grand Prix 5: Opera 11.50, Firefox 5, Chrome 12:
Recent Events
07/20/11: Apple Releases version 10.7 of Mac OS X, dubbed Lion, along with Safari 5.1
08/02/11: Google Releases Chrome 13
08/16/11: Mozilla Releases Firefox 6
08/25/11: Steve Jobs resigns as Apple's Chief Executive Officer. Contrary to what many speculated, Apple's stock remains strong.
Recent Drama
08/13/11: A Mozilla developer incites fear and chaos by suggesting the removal of version numbers altogether.
08/15/11: Microsoft Internet Explorer 9 is declared the Web browser most safe from phishing.
08/16/11: Google refutes the validity of that report.
Mac OS X
Back in July of last year, we threw Web Browser Grand Prix (WBGP) contenders Chrome, Firefox, and Opera onto an Ubuntu Linux track in Web Browser Grand Prix 2: Running The Linux Circuit. The results were compared to those of their Windows 7 counterparts from Web Browser Grand Prix 2: Top 5 Tested And Ranked. As the “Linux guy,” doing that article seemed perfectly natural to me. After all, how Web browsers perform in Windows really didn't matter to me, personally.
What we didn't see coming was the number of requests for a Mac-based Web Browser Grand Prix, and the calls for us to run Safari on OS X haven't stopped since.

In case you didn't notice, this is Web Browser Grand Prix VI, not Web Browser Grand Prix 6. That's because the twist this time is Mac OS X. We're running Chrome, Firefox, Opera, and Safari on Mac OS X, along with the usual suspects on Windows 7.
Tom's Hardware is going Mac?
That's not it at all. We said we're running Chrome, Firefox, Opera, and Safari, on Mac OS X. We did not say we're running them on a Mac. We're using the same Core i5-based desktop test system used for many of our other software-based stories. It just so happens we had OS X Snow Leopard testing in mind when it came to designing a reference cross-platform test system.
WBGP Test Suite v6.0
Once again, we tweaked our test suite for this story. The new composite page-load time tests are improved, expanded, and updated. There are all-new WebGL benchmarks, and Sputnik is replaced by Ecma test262. The methodology of the Maze Solver benchmark and memory management tests is improved to better reflect real-world usage scenarios. Enhanced placing tables and improved analysis round out the changes.
Which Web browser is best? Which operating system holds Web browsing supremacy? We'll answer that. But before we fire the starting pistol, let's take a deeper look at the contenders and course.
- Crowning A Web-Browsing King In Windows 7 And OS X
- The Contenders
- A Spotlight On Lion's Safari
- Hardware And Test Setup
- Performance Benchmarks: Startup Time
- Performance Benchmarks: Page Load Time
- Performance Benchmarks: JavaScript, DOM, And CSS
- Performance Benchmarks: Flash, Java, And Silverlight
- Performance Benchmarks: HTML5
- Performance Benchmarks: HTML5 Hardware Acceleration And WebGL
- Efficiency Benchmarks: Memory Usage
- Efficiency Benchmarks: Memory Management
- Reliability Benchmarks: Proper Page Loads
- Conformance Benchmarks: HTML5, CSS3, JavaScript, And DOM
- Placing Tables
- Analysis Tables
- Two Winners: One In Windows 7, One in OS X

thank you, workin' on it
chrome13 completely obliterats it.
and firefox 8/9 are still a memory hog.
not really surprised by poor show of ie9. moat updates it gets are "security updates".
Yeah? And exactly what principle would that be?
Bring back the Google Dictionary, otherwise I will use Bing Search, Firefox and Facebook instead of Google Search, Chrome and G+.
According to the graphic on "Reliability Benchmarks: Proper Page Loads" on MacOS Firefox is actually second, not third.
thank you, workin' on it
These "browser" GP are getting more and more complete and the're always very interesting.
I have to say, I am a bit surprised to see FF being so close to Chrome now: kudos to Mozilla.
I have been using FF since 1.0 and only recently coupled it with Chrome (it is just convenient for me to have 2 completely different setups).
FF 7.0 should have a significant boost in memory efficiency: if everything else stays the same, we´ll have a new champion ...
But if anythin is clear from these reviews, is that nothing stays the same for very long in the browser´s domain (well, except IE).
Looking forward to GP7, whenever that will be.
You should've put more emphasis on the actual scores and performances in tests rather than count the times when certain browsers placed 1st. Thus a browser that had a small advantage in more and minor tests and at the same time severe handicaps in more important but fewer tests would seem better, when technically it is not. Suggestion: tie all the candidates when the differences between them in a certain test are less than a single digit percent. Good article anyway.
And to think Apple hates Flash...
There are no points in the analysis tables. They simply list how each browser rates per category of testing. The 'Strong' part of the table was added a long time ago and it basically means that it's right up there with the winner in terms of performance. When we get a solid point-based scoring system figured out 'Winner' will only receive a minor boost above 'Strong', whereas 'Strong' will receive a significant boost above 'Acceptable', and 'Acceptable' above 'Weak'. We're not there yet, but we're getting closer with every WBGP. The composite tests are a BIG step in that direction, and the new benchmark rankings further lay the groundwork for a fair scoring system which accurately reflects scale.
The analysis tables were created to balance the raw placing tables. The problem with what you're saying is that you would have to decide which categories are more important than others. Is JavaScript more important than CSS? Is HTML5 more important than Flash? This is going to depend on who you ask. People who only watch Netflix with an HTPC will put mega emphasis on Silverlight perf, whereas the chronic YouTuber will be more concerned with Flash, and devs are going to gravitate towards standards conformance. Ranking benchmarks based on the importance of what they test isn't a one-size-fits-all type of thing with Web browsers. As far as your other suggestion, dealing with practical ties, this is something we definitely want to look into moving forward. Thanks!