Since its debut, Safari has offered Apple Mac users hassle-free browsing, standards-friendly HTML rendering, and a number of thoughtful and handy features to make surfing the Web just a little bit more fun. Its triumphant new version continues all these trends with style--and bolts on a jumbo jet engine's worth of pure speed.


Remember the DeLorean from Back to the Future, leaving tracks of flame in its wake as it shot into another era? That's the impression one gets when comparing Safari's performance to that of its closest rivals.

On a 2GHz aluminum MacBook ( Macworld rated 4 out of 5 mice ) with the standard 2GB RAM, I ran Safari 4 through a battery of tests to measure how quickly it rendered XHTML and CSS and performed basic JavaScript operations. In addition to comparing it to its biggest released rival, Firefox 3 ( Macworld rated 4.5 out of 5 mice ), I measured its performance against the latest beta of Firefox 3.5 and a development version of Google's forthcoming Chrome browser. In every test, Safari easily beat all its competitors at the very least, and absolutely trampled them at best.
In XHTML rendering, Safari's 0.54 seconds clocked in at nearly seven times faster than Firefox 3's 3.42 seconds, and still thrashed Firefox 3.5's 2.82 seconds. Even Chrome, which uses the same WebKit rendering engine that powers Safari, could only manage a respectable 1.14 seconds.

In the CSS test, Safari again walloped all comers with a 35ms load time, compared to 50ms for Chrome, 355ms for Firefox 3, and 498ms for Firefox 3.5. And Safari's new Nitro JavaScript engine similarly lived up to its name, completing the same set of operations in 99ms that took Firefox 3 540ms, Firefox 3.5 354ms, and Chrome 375ms.
In addition to superlative speed, Safari also tops the competition in its strict compliance with Web standards. Living up to Apple's hype, Safari 4 is indeed the only current Mac browser to pass the Acid3 Web standards test with flying colors. Chrome managed to match Safari 4's perfect 100-out-of-100 score, but got a linktest error that Safari didn't. Firefox 3 scored a 71, while Firefox 3.5 got a much closer 93.

Not surprisingly, Safari also got top marks for compatibility with selectors for the emerging CSS3 standard for online style sheets, albeit in a tie with Chrome. Both browsers were able to handle all 578 selectors thrown at them by an automated online test. Firefox 3 accepted only 371, while Firefox 3.5 scored a much more impressive 576.

Apple touts Safari's ability to handle the still-in-development HTML 5 markup standard, and in most respects, it's right. Safari 4 had no trouble rendering any pages from a gallery of sites already using HTML 5, and it could even display some--but not all--of the cutting-edge pages from a gallery built specifically for Google's Chrome. (It did seem to have trouble with HTML 5's emerging Video and Audio tags, but that technology's admittedly still in its infancy.) Safari also does a great job with animation, drop shadows for text, and other new tricks vying for inclusion in the final CSS3 style sheet standard, feats only Chrome and its shared WebKit engine can match.