New IE8 still the slowest browser

Microsoft's final code comes in dead last in JavaScript benchmark tests

By Gregg Keizermay be talking up the performance boost it gave to its just-launched Internet Explorer 8, but the new browser remains the slowest of the top five on the market, benchmark tests show.

According to JavaScript rendering tests run by Computerworld, the final version of IE8 is only slightly faster than the browser's Release Candidate 1, which Microsoft delivered in January.

Computerworld ran the SunSpider benchmark tests in Windows XP three times for each browser, then averaged the scores.

Google Inc.'s Chrome led all browsers in the SunSpider tests, making it more than four times faster than IE8. Coming in second was Mozilla Corp.'s Firefox 3.0.7, followed by Apple Inc.'s Safari 3.2.2 for Windows and Opera Software's Opera 9.63.

Firefox proved to be 59% faster than IE8, while Safari was 47% faster. Opera, the slowest non-Microsoft production browser, was still 38% faster than IE8.

Microsoft, however, has continued to downplay benchmarks such as SunSpider, and instead has promoted page-load time trials that pit browsers against each other in rendering the Web's top 25 destinations. Last week, Microsoft claimed that IE8 loaded more sites faster than either Chrome or Firefox.

At the time, Microsoft's James Pratt, a senior program manager for IE, conceded that the differences were slight. But in an interview yesterday, Pratt called IE8 "highly competitive" with other browsers, and dubbed it "the fastest version of IE that we have ever released."

But he also acknowledged that speed is important to users. "We know that speed is critical to people who are using browsers today," Pratt said, "and we recognize that users have a choice when it comes to browser."