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Web Browser Grand Prix: Firefox 15, Safari 6, OS X Mountain Lion

Reliability, Responsiveness, And Security


Our reliability test is conducted after loading 40 tabs. We open them all simultaneously and record how many pages require a reload due to broken formatting or missing elements. The best score a browser can achieve here is zero, and the worst is 40.

Once again, Opera shows itself to be the rock-solid option, with only one reload required on each OS. Safari takes second place on Mountain Lion with an average of eight reloads, followed by Firefox in third with ten and Chrome in fourth with a whopping 21 reloads on OS X. The second-place finisher for Windows 7 is IE9 with 12 failures, followed by Chrome and Firefox in a tie for third, each requiring 13 reloads.


The responsiveness of each browser is gauged by its behavior during the 40-tab memory usage tests. While we're not timing how long each browser can load all 40 tabs, we are looking to see how quickly we can use the browser without scroll lag and other hang-ups while the tabs are still loading.

IE9 is once again the only browser to actually crash during the 40-tab load. Opera again is speediest to become responsive, followed by Firefox, then Chrome. Chrome is noticeably worse on OS X than Windows 7, while Safari is about equal to Firefox. We're calling Opera the winner on both platforms, followed by Firefox and Safari with strong finishes. Chrome is merely acceptable, while IE9 is clearly weak.


BrowserScope Security contains 17 pass/fail security checks.

Chrome takes first place by passing 16 out of the 17 tests. Safari earns second place with 14 out of 17 tests passed. Internet Explorer passes 13 tests to place third, followed by Firefox in fourth place with 12 tests passed. Opera passes 10 of the 17 tests, earning the Norwegian Web browser another last-place finish.