Like it or not, the modern internet is funded mostly by advertising revenue. The ads you see aren’t just limited to the annoying pop ups scattered across the page. There are also tracking services connecting in the background to follow you around the web in order to show more relevant and targeted ads. Ad-blockers have existed for a long time, but as the complexity of the web has grown, so has the memory footprint of ad-blockers. A new ad-blocking extension called µBlock has been gaining ground on Chrome and just recently came to Firefox and Safari. It’s like the other ones but, you know, smaller.

Mature browsers like Chrome and Firefox often have a reputation for feeling sluggish when you load them down with extensions, but it has been pointed out that some ad-blocking tools actually gobble up RAM like there’s no tomorrow. Specifically, the popular Adblock Plus extension loads a 4MB CSS stylesheet on every webpage to block the ads on it. That’s fine, except when pages use iframes (and most do) that are essentially embedded web pages. It’s rather a catch 22 where trying to block the ads that are slowing your system down can actually slow your system down in a different way.



That’s where µBlock comes in. The developers have gone to great lengths to show that this open source alternative ad-blocking extension for Chrome, Firefox, and Safari has a smaller footprint than the competition. There are graphs and everything that appear to show how much lighter µBlock is , but of course we don’t know the exact conditions these tests were run under. I ran µBlock alongside Ghostery and Adblock Plus to find out.

Chrome has a handy task manager interface under the “more tools” menu. Here you can see how much memory each page, app, and (importantly) extension is using. Memory usage for ad-blockers will vary depending on how many tabs you have open, but they all jump when you first install or update them as new filter lists are downloaded. That’s how they know what’s an ad and what’s a picture of a cat (or whatever you’re looking at).



I use Ghostery, but I only enable it on sites that are unusable or particularly annoying without blocking ads. After getting all three extensions updated and letting them idle, Ghostery actually had even lower memory utilization than µBlock. Adblock Plus was already much higher, though. After browsing for a bit, µBlock seemed to settle down and sunk below 40MB of memory with about a dozen pages open. Ghostery was just a little higher, and Adblock Plus was at almost 70MB. So µBlock does seem to eat much less RAM than ABP, but it’s roughly in-line with Ghostery, which is rather popular too. The footprint of individual pages changed by similar margins depending on which extension was enabled.

Users seem quite sure that µBlock makes their browsers more responsive and smoother, but I don’t know that I see any difference. This sort of measurement is arbitrary by nature, but it makes sense that having a lot of tabs open with Adblock Plus could get out of hand. However, Ghostery is roughly as efficient as µBlock and its interface is worlds better. So µBlock looks like it’s better than ABP in terms of performance, but it’s not magic or anything. I would still wager there’s some element of the placebo effect involved here.

I use the regular Chrome ABP, didn't notice any impact on the browsing speed, but I will certainly try the new app.
However, I always make sure to disable these sort of blockers when watching youtube videos in order to support content creators.... I hope everyone does the same.