Foreword: Using a blocker is NOT theft. Do not fall for this creepy idea. The ultimate logical consequence of "blocking = theft" is the criminalisation of the inalienable right to privacy.

See releases page for recent changes. See Wiki for more information.

An efficient blocker for Chromium-based browsers. Fast and lean. Written from scratch. Development through benchmarking.

µBlock is not an "ad blocker", it's a blocker in the broad sense, which happens to block ads through its support of Adblock Plus filter syntax. µBlock extends the syntax.

EasyList, Peter Lowe's Adservers , EasyPrivacy are enabled by default when you install µBlock. Many more lists are readily available to protect yourself from trackers, analytics, data mining, and more ads. Hosts files are supported.

Ads are just the visible portions of privacy-invading apparatus entering your browser when you visit most sites nowadays.

My main goal with µBlock is to help users neutralize as much as can be privacy-invading apparatus (of which ads, "unintrusive" or not, are just the visible portion) for users who do not want to deal with more technical means like µMatrix.

µBlock: on average, it really does make your browser run leaner

^{Details of the benchmark available in this LibreOffice spreadsheet.}

[Important note re memory usage: there is currently a bug in Chromium 39+ which causes a new memory leak each time the popup UI of an extension is opened. This affects all extensions. Just so you are informed memory figures won't be too reliable as soon as you opened even only once the popup UI of an extension. (In all my benchmarks I of course avoided to do this).]

µBlock: it is also easy on the CPU

^{This gives an idea of the CPU overhead added by extensions relative to each other.
Details of the benchmark available in this LibreOffice spreadsheet.}

Being lean doesn't mean blocking less.

^{For details of benchmark, see latest µBlock and others: Blocking ads, trackers, malwares.}

From the Chrome store, the Opera store, or manually.

To benefit from the higher efficiency, it is of course not advised to use an inefficient blocker at the same time. µBlock will do as well or better than the popular blockers out there.

Also of interest: About the required permissions.

I think it is pretty obvious, except for this I suppose:

The big power button is to disable/enable µBlock for the specific hostname which can be extracted from the URL address of the current page. (It applies to the current web site only, it is not a global power button.) The state of the power switch for a specific site will be remembered.

The right-hand screenshot shows optional dynamic filtering at work.

µBlock is born out of HTTP Switchboard. All the niceties of HTTPSB have been removed, and what is left is a straightforward blocker which support EasyList and the likes, and also support host files. Cosmetic filters ("element hiding") are supported.

There is nothing more to it. But it does what popular blockers out there do, at a fraction of CPU and memory usage for the same blocking power. Also, no unique user id and no home means no phoning home (some popular blockers do this, just be careful).

Free. Open source. For users by users. No donations sought.

Without the preset lists of filters, this extension is nothing. So if ever you really do want to contribute something, think about the people working hard to maintain the filter lists you are using, which were made available to use by all for free.

You may contribute by helping to translate this project. I created an entry on Crowdin, where you may contribute to the translation work.

GPLv3.