Contrary to Apple's claims, the newest version of Safari is not the world's fastest browser, benchmark scores show. But it is dramatically faster than rivals being built by Mozilla and Microsoft.
According to JavaScript rendering tests run by Computerworld, the public beta of Safari 4 is in a virtual dead heat with the most recent edition of Google's Chrome, but is 38 percent faster than the newest version of Firefox, more than three times faster than the production edition of that open-source browser, and over five times faster than Microsoft's Internet Explorer 8.
Computerworld ran the SunSpider JavaScript benchmark suite in Windows XP three times for each browser, then averaged the scores.
Safari 4, which Apple released Tuesday as a public beta , scored just slightly higher than Chrome 2.0.164.0, a developer-only build of Google's browser that was issued only last week. The difference, however, was minute: Google was only about 7 percent faster. Although Chrome and Safari are both built around the same open-source WebKit engine, they use different JavaScript engines. The former features Google's own V8 engine, while Safari 4 relies on Apple's new Nitro.
That new engine was most in evidence when Safari 4's scores are compared to those of Safari 3.2.2, the current shipping version on Windows: The beta of Safari 4 was about 3.7 times faster.
Safari 4 also proved faster than the newest Firefox, a nightly build in the run-up to Firefox 3.1, although at just 38 percent faster its edge was much smaller.
It easily beat Firefox 3.0.6, Mozilla's production browser, and IE8 Release Candidate 1 (RC1), Microsoft's latest public release of its still-under-construction successor to the three-year-old IE7. According to SunSpider's tests, Safari 4 is nearly 3.5 times faster than Firefox and about 5.6 times faster than IE8.
When IE7 is brought into the picture, Safari 4 looks lightning-quick: Apple's browser is more than 76 times faster at completing the JavaScript tests than Microsoft's.
Most browser makers have been aggressively promoting improved JavaScript performance for months. Google, for example, bragged up Chrome's when it debuted the browser last September , while Mozilla has been talking up Firefox 3.1's TraceMonkey engine since August.
Microsoft, however, has disparaged the benchmark bragging as a "browser drag race" that it's not interested in joining. Instead, senior product manager James Pratt has tried to steer the conversation away from JavaScript and toward a more subjective interpretation.
"We're at the point, with what people do in the browser, that users can't really tell the difference between browsers," he has argued. "Beyond building a performance lab, which we've done, it's very difficult to tell which browser is fastest. The reality is that for most users, they'll all be comparable."
On the Mac, where Safari doesn't have to compete with Google — Chrome has yet to be ported to Apple's operating system — the beta of version 4 is almost twice as fast as Firefox 3.1 Beta 2 and nearly four times faster than Firefox 3.0.6, according to SunSpider tests run on a 2.4GHz "unibody" MacBook.