Firefox 4's first beta is 27% faster than Mozilla Corp.'s more stable browser, Firefox 3.6.6, but it still lags behind some of its rivals, including Chrome, Opera and Safari, benchmark tests show.
According to tests run by Computerworld, Firefox 4 Beta 1 gained significant performance ground over its predecessor yet still has a long way to go to catch the leaders.
Mozilla implicitly acknowledged that on Tuesday, when it launched Firefox 4's first general public preview. "This is just the beginning for performance improvements in Firefox 4," said Mike Beltzner, director of Firefox, in an entry on the Mozilla blog earlier this week.
Apple Inc.'s Safari 5 remained the speed champ, but just barely: The Windows version of Safari was only 2% faster than Opera Software ASA's namesake desktop browser. Last month, Safari 5 dethroned Opera, which had held the crown since February.
Opera 10.60, which landed last week, was nearly neck-and-neck with Safari, a better showing than in early June when Safari proved 9% faster than Opera 10.53 on Windows.
Google's Chrome 5, meanwhile, was 40% faster than Firefox 4, but it was slower than either Opera or Safari, putting it in the middle of the pack.
Microsoft figures to pick up the pace with IE9, the version that's been released only in rough developer preview formats so far. The company has not announced a beta ship date, much less a final launch timetable, but a recently leaked presentation touting Windows 8, the next version of Microsoft's desktop operating system, claimed that IE9 will shift into public beta next month.
Firefox may not be the fastest browser, but it's still the second-most-popular browser on the planet. In June, Firefox accounted for 23.8% of all browsers used to reach sites monitored by Web analytics firm Net Applications. Internet Explorer gained ground at a record pace, which is highly unusual, to end the month at 60.3%. Chrome, Safari and Opera held usage shares of 7.2%, 4.9% and 2.3%, respectively.
However, Mozilla's browser has lost share in five of the last seven months since peaking in November 2009.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, or subscribe to Gregg's RSS feed . His e-mail address is email@example.com.