The Best Adblockers for Firefox & Chrome

There was a time when there were no ads on the Internet. Those were the days. But making and updating websites takes time and money. Marketing companies saw the opportunity and jumped on it. That’s also when adblockers were born. But what are the best adblockers for both Chrome and Firefox browsers?

Our research shows the following are the best adblockers for Firefox and Chrome, in alphabetical order:

• AdBlock
• Adblock Plus
• AdBlocker Ultimate
• AdGuard
• Ghostery
• uBlock Origin

All adblockers tested are also free to use. If you want to see how they stack up against each other, and which one we think is the best, keep reading.

Use Adblockers Fairly

Please think about us, people just like you, trying to pay our bills before you use an adblocker on sites like ours. We try abnormally hard to find the right balance between having ads to pay the bills and not annoying you so that you leave us.

So please, if you do choose to use an adblocker, make sure to whitelist our site.

Now that’s said, let’s look at the best adblockers to use on sites that don’t respect you as much as we do.

How Do We Know Which Adblocker Is Best?

We can’t test all the adblockers available, so we narrowed the list to 6. To do this, we gathered the number of downloads, the number of reviews, and the average rating out of 5 stars for adblockers from the Firefox Add-Ons and Chrome Web Store Extensions sites.

Then we used our Review Factor formula to show us which adblockers were arguably the best. The highest Review Factor possible is 100. This was done to remove the bandwagon effect of people selecting the most downloaded adblocker that has a good star rating.

Review Factor = ((Reviews / Downloads) x Average Star Rating) x 100

After the top 6, the Review Factor dropped off sharply, so it wouldn’t be helpful to you to include anything beyond that. Then came the testing.

The following is our testing methodology:

1. Do a clean install of Chrome and Firefox.
2. Install a single adblocker with its default settings.
3. Test using the sites canyoublockit.com and adblock-tester.com
4. Calculate the Test Average using:
   Test Average = (CanYouBlockIt Extreme Avg + Adblock Tester Avg)/2
5. Uninstall the adblocker
6. Empty the browser cache and restart the browser to make sure it’s like new before performing steps 2 through 7 on the next adblocker to be tested.
7. Calculate the Overall Score out of 100.
   Overall Score = (Review Factor + Test Average)/2

6. AdBlock Plus (Chrome, Firefox)

Browser	Chrome	Firefox
Score	35	32

AdBlock Plus also subscribes to the fair-play ads philosophy. They’ve even created an independent committee called Acceptable Ads. It’s not clear whether they are actively working with any other adblockers than Adblock Plus, so the independence of the committee is debatable.

CanYouBlockIt Results

• Presence was detected (Chrome and Firefox)
• Allowed pop-under ads (Chrome and Firefox)
• Allowed direct link ads (Chrome and Firefox)

AdBlock Tester Results

• Allowed Google Analytics (Chrome and Firefox)
• Allowed Sentry and Bugsnag error monitoring (Chrome and Firefox)
• Allowed the downloading of Flash banners, gifs, and static images, but blocked the display of them (Chrome and Firefox)

5. AdBlock (Chrome, Firefox)

Browser	Chrome	Firefox
Score	38	32

AdBlock can be used for free or you can make a donation. You can get a refund within 60 days if you’re not happy with AdBlock. AdBlock is a fair-play adblocker, meaning it tries to block the most obtrusive and invasive ads while allowing more palatable ads so that the sites you’re viewing can still have some income.

CanYouBlockIt Results

• Presence was detected (Chrome and Firefox)
• Allowed pop-under ads (Chrome and Firefox)
• Allowed direct link ads (Chrome and Firefox)

AdBlock Tester Results

• Allowed Google Analytics (Chrome and Firefox)
• Allowed Sentry or Bugsnag error monitoring (Chrome and Firefox)
• Allowed the downloading of Flash banners, gifs, and static images, but blocked the display of them (Chrome and Firefox)

4. Ghostery (Chrome, Firefox)

Browser	Chrome	Firefox
Score	39	40

Ghostery claims to do the adblocking that all the other adblockers do and speed up page loading. We weren’t able to test that, but the extension does allow you to see the download time of a page.

What’s really interesting is that Ghostery is open-source. Generally speaking, making software open source leads to it becoming better and more secure. Yet it seems like a bold step as advertisers may use that to find a way to circumvent Ghostery.

CanYouBlockIt Results

• Allowed banner ads (Chrome and Firefox)
• Allowed direct link ads (Chrome and Firefox)

AdBlock Tester Results

• Allowed Flash banners to load and display (Chrome)
• Allowed Sentry error monitoring (Chrome and Firefox)
• Allowed the downloading of gifs and static images, but blocked the display of them (Chrome and Firefox)

3. AdGuard (Chrome, Firefox)

Browser	Chrome	Firefox
Score	40	40

AdGuard employs a filtering database with more than 1 million phishing and malware websites in it. This means it not only employs traditional adblocking but can protect you from some nasty sites.

CanYouBlockIt Results

• Presence was detected (Chrome and Firefox)

AdBlock Tester Results

• Allowed Google Analytics (Chrome and Firefox)
• Allowed Sentry and Bugsnag error monitoring (Chrome and Firefox)
• Allowed the downloading of gifs and static images, but blocked the display of them (Chrome and Firefox)

2. uBlock Origin (Chrome, Firefox)

Browser	Chrome	Firefox
Score	43	43

uBlock Origin is another open-source adblocker, that claims to be, “a wide-spectrum content blocker with CPU and memory efficiency as a primary feature.” What they’re saying is that other adblockers may use more resources and slow your computer down. We were unable to test that, as it was beyond the scope of this article.

CanYouBlockIt Results

• Allowed direct link ads (Chrome and Firefox)

AdBlock Tester Results

• Allowed Flash banners to load and display (Chrome)
• Allowed Flash banners to load but didn’t display (Firefox)
• Allowed Sentry error monitoring (Chrome and Firefox)
• Allowed the downloading of gifs and static images, but blocked the display of them (Chrome and Firefox)

1. AdBlocker Ultimate (Chrome, Firefox)

Browser	Chrome	Firefox
Score	55	32

AdBlocker Ultimate touts itself as, “the most effective adblocker there is!”. We haven’t tested every adblocker available, yet AdBlocker Ultimate tops our list. There is no predefined list of acceptable ads for AdBlocker Ultimate. It strives to block everything. Their work is supported by a name-your-price system allowing you to donate what you think is fair via PayPal.

CanYouBlockIt Results

• Presence was detected (Chrome and Firefox)

AdBlock Tester Results

• Allowed Bugsnag error monitoring (Chrome and Firefox)
• Allowed the downloading of gifs and static images, but blocked the display of them (Chrome and Firefox)

What AdBlocker Do You Use?

As we mentioned above, there are a lot of adblockers out there. What do you use? Is it different from the ones on our list? What do you like most or least about your adblocker? Let us know in the comments below.