Firefox 13 is out and it's all about speed, Opera 12 has added a few new features, and Chrome is still cranking out new versions, so we thought it time for another browser speed test. We've once again pitted the four most popular Windows web browsers against each other in a battle of startup times, tab loading times, and more, with some shocking results.


These tests are now out of date. As usual, you can see our most recent batch of speed tests at lifehacker.com/browserspeedtests.


We've been testing browsers for awhile, and we've refined our method pretty well. It's a good mix of both manually timed user experience measures and hardcore JavaScript and CSS benchmarks, plus some new tests aimed at features like Chrome's prerendering or Firefox's on demand tab loading can really do. All tests take place on Windows (which is why we didn't test Safari—it isn't very popular on Windows, and testing the Mac version wouldn't give it equal footing. We'll do a Mac-wide browser speed test the next time around).

How We Test Web Browsers We've been using the same basic methodology since our first set of browser speed tests, but we've… Read more

As always, remember that speed is not the only thing each browser has to offer. Each browser has a number of unique features and characteristics, all of which you should factor into making your choice of which to use. However, while most features can be listed on their home pages, you can't easily compare their speed just from each browser's changelog, and that's why we've put this together. It's just one more way to compare the browsers as you make your decision. Also keep in mind that everyone's computer is different, and your numbers may differ from ours, but the comparison between the numbers should be the same.

Cold Boot-Up Winner: Opera!


Once again, we've slightly tweaked how we measure cold boot-ups, this time measuring until the moment you can actually type in the address bar and start visiting pages (since that's when most people will consider the browser "usable"). Coupled with all the new updates, this produced some very different results, with Opera coming out way ahead of the competition, ready to use in less than 2 seconds. Chrome came in second at about 4 seconds, the other browsers trailing further behind.

Tab Loading Winner: Firefox!


Our test of loading nine tabs, from Lifehacker to Facebook to Hulu and Gmail, Opera 12 shockingly took much longer than usual—despite supposed speed increases—while Firefox dropped enough time to put it into the first place slot. Chrome continued to be agonizingly slow.

URL Loading Winner: Chrome!


Not surprisingly, Chrome took home the prize for visiting sites from the address bar, thanks to its awesome prerendering feature. While most browsers were pretty quick, Chrome was near instantaneous, as long as you had visited that page once during that session. Firefox and IE took second and third place, with Opera nearly doubling their times.

Cold Restore Winner: Opera!


In an effort to test the benefits of Firefox's new on demand tab loading and Opera's similar managed tab loading feature, we took the same nine tabs as above, saved them in a session, and did another cold boot of the browser on restart, timing the time it took to automatically restore that session of tabs. This was a tough one to test, since it's really about when the browser becomes easily usable more than anything. That means Firefox and Opera smoked the others, since they only loaded one or two tabs at a time, while Chrome and IE tried to load all the other tabs at once, crushing the browser and making it slow down. Opera won this round because it was the fastest to load that first tab and become usable, while still loading your other tabs slowly in the background. Firefox took an extra second or so, even though it only had to load one tab and stop.

JavaScript Winner: Chrome!


Not much changed in the JavaScript and CSS realms this time around. Chrome once again took home the gold in JavaScript performance, with Firefox coming in a distant second, not far from the other browsers.

DOM/CSS Performance Winner: Opera!


Like the JavaScript tests, there's nothing new here. Opera once again obliterates the other browsers with seriously awesome CSS performance.

Memory Usage (with Nine Tabs Open) Winner: Firefox!


Firefox continues to work on memory usage improvements, and even Opera shaved some serious MB off its usage this time around. After a few minutes, the memory usage of IE and Chrome leveled out around 400MB, while Firefox was closer to 310MB and Opera at 325MB.

Memory Usage (with Nine Tabs and Five Extensions) Winner: Firefox!


This was the really shocking result this time around: Firefox may not have improved a ton without add-ons, but when you pile on five different add-ons, it's memory usage is insane—because it barely goes up. The other browsers had their memory usage jump nearly 200MB, while Firefox's only jumped up by 60MB, making it a very clear first place winner. Its UI may still feel a little laggy, but when it comes to actually conserving memory, Firefox kicks butt.

Overall Scores

We debated ditching "overall scores" this time around, since it becomes harder and harder to tally them up fairly, and it's more important to look at each individual category than it is some arbitrary score. But everyone likes a winner, so we've kept this section at the end for those of you handing out trophies, and the scores are:

Firefox: 81% Opera: 68% Chrome: 62% Internet Explorer: 41%

Firefox's new tabs on demand feature and its expedited tab loading brought it into first place, above last time's winner, Chrome. Opera caught up to Chrome and even blew past it with its speed improvements, while Internet Explorer once again took a fairly distant last place. As we said, you should look at the individual scores above to see which browser is faster in the areas you care about—if you don't like Firefox's new tabs on demand, for example, Chrome may be "faster" for you. As usual, we're seeing that each browser is focusing on specific areas of improvement: Firefox with memory management, Opera with start times and CSS, and Chrome with its JavaScript and prerendering features—so wherever you're feeling the weight of your current browser, that might be a good place to see who's a faster choice.


Our tests aren't the most scientific on the planet, but they do reflect a relatively accurate view of the kind of experience you'd get from each browser, speed-wise. Let us know if your experience differs-or if the speed losses are worth the browser's other features-in the comments.