Pros
Cons
Our Verdict

Safari 5.1 didn’t age gracefully on my older hardware. While Apple’s Web browser still posted fast benchmarks, it grew teeth-grindingly sluggish when loading or navigating multiple tabs. Under Lion, Safari 6 similarly left me more aggravated than appreciative.
But under Mountain Lion, the new Safari became a whole different animal.
The king is dead
Safari 6 packs relatively few new features for a major browser update, and most of its shiny new bells and whistles need Mountain Lion to run properly.
But even under Lion, you’ll see one of Safari 6’s biggest changes immediately. Like Firefox ( ), Safari has consolidated URLs and searches in a single bar at the top of the screen. You search with Google by default, but can specify Yahoo! or Bing in preferences. Unlike Firefox, Safari doesn’t keep a vestigial search box hanging out next to its all-in-one window for no apparent reason. I liked Safari’s useful, unobtrusive implementation of this idea.

Safari 6 also treats tabs differently. They now expand to take up equal portions of the browser window’s full span. With only two open, tabs look almost comically broad, but still work as well as ever. The rest of the browser seemed to wheeze under Lion. It would occasionally take ages to load a page. If I tried to switch to another tab during that tedious wait, I’d see a blank white screen, even if the other page had previously loaded. Even more surprisingly, benchmark tests showed that Safari 6 posted 17 percent slower JavaScript performance under Lion than Safari 5.1.7. (Scores in other tests stayed constant or grew slightly; see below.) Then I installed Mountain Lion—and Safari 6 became a much better browser.
Hail to the king
Under Mountain Lion, Safari 6 attains striking poise. The blue progress bar once stuttered across the URL bar; now it glides. Pages slide even more smoothly as you swipe (on a trackpad) to navigate. And the contents of a page seem to pour into place as it loads.
Aside from an odd habit of a split-second fade-out and fade-in while the browser reloads a page you’ve just moved forward or back to, everything feels fast and fluid, even on a 2008 laptop. Apple has made Safari 6 on Mountain Lion the Mac’s most visually polished browser.
That slickness extends to Tab View, another Mountain-Lion-only improvement. Pinch the screen when using a trackpad (or select View > Show All Tabs, or press Shift+Command+ on your keyboard), and your current window shrinks into a scrolling cavalcade of all your tabs. This beats puzzling out one tab’s truncated name amid a hodgepodge of others, and it’s more usable and graceful than Opera’s visual tabs.

Reader mode gave me headaches in Safari 5, but works like a charm here. After I clicked the new button at the right edge of the URL/search bar, multi-page stories and slideshows from various sites loaded in a flash, each new page arriving as I scrolled to the end of the current one. Ad-hungry websites may groan, but I relished reading a single article without multiple clicks.
I would have appreciated a button within Reader view to add that page to my Reading List, which now downloads and stores articles so that you can peruse them offline. (The Reading List icon steadily fills with blue to indicate save progress—a small, nifty detail.)
Instead, I had to use the iOS-style Share button at the top of the page, which also adds bookmarks and sends pages via Mail, Messages, or Twitter. Apple promises Facebook compatibility soon.
That isn’t the only Safari 6 upgrade still under construction. On its Web site, Apple promises that Cloud Tabs will let you pick up browsing where you left off on your iPhone or iPad. But that feature won’t fully arrive until iOS 6 appears this fall. For now, it only works with other Macs.
Among other new features, Apple boasts better support for HTML5 audio and other emerging standards; more features for Chinese-language browsers; and support for the voluntary, little-adopted “Do Not Track” privacy protocol.
Not quite a great leap forward
In benchmark tests on a 2GHz aluminum MacBook with 2GB of RAM, Safari 6 posted mixed results. It still rules in HTML5 rendering, matching or beating its previous scores (and every other browser tested) in vector and bitmap graphics and text rendering. But in JavaScript, Safari 6 falls behind not only its previous version, but also the latest incarnations of Chrome and Firefox. On Mountain Lion, its SunSpider score improved on Lion’s by about 7 percent, but still trailed Chrome by roughly 30 milliseconds, and Firefox by around 15. Mountain Lion also added 10 points (out of 500) to Safari 6’s HTML5 standards compliance on Lion, which in turn improved on Safari 5.17 by 47 points. But it fell 17 points shy of Opera’s latest edition, and 25 points behind Chrome.
Benchmarks: Safari 6
Browser | SunSpider | Acid3 | HTML5 Vector | HTML5 Bitmap | HTML5 Text | HTML5 Compliance |
---|---|---|---|---|---|---|
Safari 6.0 (Mountain Lion) | 353.7 | 100 | 34.53 | 55.05 | 20.39 | 391/11 bonus |
Safari 6.0 (Lion) | 380.0 | 100 | 31.44 | 56.97 | 19.21 | 381/11 bonus |
Safari 5.1.7 | 323.8 | 100 | 31.80 | 54.54 | 19.90 | 334/11 bonus |
Opera 12 | 393.3 | 100 | 25.22 | 55.98 | 20.17 | 400/9 bonus |
Firefox 14.0.1 | 338.8 | 97 | 2.86 | 13.65 | 19.29 | 345/9 bonus |
Chrome 20 | 324.6 | 97 | 13.94 | 24.04 | 16.24 | 414/13 bonus |
Best results in bold. Reference browsers are in italics. The SunSpider JavaScript results are in milliseconds; shorter times are better. The Acid3 result is a score out of 100. HTML5 Vector, Bitmap, and Text test results are in frames per second; higher is better. HTML5 Compliance is a score out of 500.
Macworld’s buying advice
I can’t recommend Safari 6 under Lion; its few interface improvements can’t outweigh its surly performance. Under Mountain Lion, it’s a blast to use, and its relatively few additions all prove worthwhile. Other browsers may give you more raw power in some respects, but Safari still delivers the most elegant and enjoyable Web experience.
[Nathan Alderman is a writer, editor, and professional nitpicker in Alexandria, Va.]