uBlock Origin blocks ads and tracking scripts before they load on a webpage
uBlock Origin is a free extension that stops advertisements and many tracking tools from running on the websites you visit. Unlike some ad blockers, it does not sell data about what you block or show you ads of its own. You install it from the Chrome Web Store in about two minutes, then turn it on or off for individual websites as you choose.
The extension works by comparing each element a webpage tries to load — images, scripts, requests to ad servers — against lists of known ad and tracking domains. If something matches, it never reaches your browser. This means pages often load faster, use less data, and expose you to fewer tracking pixels that follow you across the internet.
uBlock Origin is maintained by a single volunteer developer and is open source, meaning anyone can read the code to verify what it actually does. It has no paid tier, no premium features, and no business model that depends on your attention or data.
Key Takeaways
- read uBlock Origin from the official Chrome Web Store by searching for it by name, then click Add to Chrome and confirm the permission prompt.
- The extension is active by default on all websites once installed, but you can pause it on individual sites by clicking its icon in your toolbar.
- uBlock Origin's default filter lists block most common ads and trackers, and you can add more lists or create custom rules if you want stricter filtering.
- The extension does not require an account, does not phone home with your browsing data, and updates its filter lists automatically in the background.
Step-by-step installation in Chrome
Open Chrome and go to chrome.google.com/webstore. In the search box at the top left, type "uBlock Origin" and press Enter. The official extension appears at the top of the results — it has a red and white shield icon and is published by the author "Raymond Hill". Click on it to open the extension page.
On the extension page, click the blue button labeled "Add to Chrome" in the top right. A popup appears asking you to confirm that you want to add the extension. It will list the permissions uBlock Origin needs — mainly the ability to read and modify the content of webpages so it can block elements before they display. Click "Add extension" to confirm. The button changes to say "Remove from Chrome", which means the installation is complete.
Chrome may show a small notification that the extension has been added. You can close this notification. The uBlock Origin icon — a red and white shield — now appears in your browser toolbar, usually in the top right corner next to your profile picture. If you do not see it when ready, click the puzzle-piece icon in the toolbar to see your list of extensions, then click the pin icon next to uBlock Origin to make it always visible.
Turning the extension on and off for specific websites
uBlock Origin is on by default for every website you visit. To pause it on a single website, click the shield icon in your toolbar while you are on that site. The icon changes color — usually to gray — and the extension stops blocking on that page. Reload the page to see the difference. Click the icon again to turn blocking back on.
You might pause uBlock Origin on a website because the site does not work properly with blocking enabled, or because you want to see ads on a site you support. Some news outlets and creators rely on ad revenue, and pausing the extension is one way to help them without paying a subscription.
Pausing the extension on one website does not affect any other website. Each site has its own on-or-off setting that persists until you change it again.
Understanding the default filter lists
When you install uBlock Origin, it comes with several filter lists already enabled. These lists are maintained by volunteers and contain the addresses of known ad servers, tracking domains, and malware sites. The default lists cover most common ads and trackers you will encounter on mainstream websites.
To see which lists are active, click the shield icon and then click the gear icon at the bottom right of the popup. This opens the settings page. Click the "Filter lists" tab. You will see a section called "Built-in" with checkboxes next to each list. The ones that are checked are currently active. The most important ones are "uBlock filters" and "Ads, privacy, malware" — these two handle the majority of blocking.
You do not need to change these settings to use uBlock Origin effectively. The defaults work well for most people. If you find that a website is broken because too much is being blocked, you can temporarily pause the extension on that site rather than disabling specific filter lists.
What uBlock Origin blocks and what it does not
uBlock Origin blocks display ads (the banners and videos you see on pages), tracking scripts (code that follows you across websites), and malware domains. It does not block sponsored content that is part of a website's own code — for example, a YouTube video that is labeled as an ad but is served by YouTube itself. It also does not block paywalls or login screens.
Some websites detect that you are using an ad blocker and show a message asking you to disable it or subscribe. uBlock Origin cannot prevent these messages, though some filter lists include rules to hide them. If a site requires you to turn off the extension to read it, you have three choices: pause uBlock Origin on that site, use a different browser for that site, or stop visiting the site.
uBlock Origin does not speed up your internet connection itself, but it does reduce the amount of data your browser downloads by not loading ads and tracking pixels. On a slow connection or a phone with limited data, this can make pages feel noticeably faster.
Keeping uBlock Origin updated
Chrome automatically updates extensions in the background, usually once a day. uBlock Origin's filter lists also update automatically — typically every few hours — so you are always blocking the newest known ad and tracking domains without doing anything yourself.
You can manually check for updates by going to chrome://extensions, finding uBlock Origin in the list, and clicking "Update" if the button appears. You can also see when the extension was last updated by clicking the "Details" button on the same page.
You do not need to reinstall or reconfigure uBlock Origin when it updates. Your settings and any custom rules you have created are preserved.
Customizing uBlock Origin if you want stricter filtering
The default settings block most ads and trackers, but you can add more filter lists if you want stricter filtering. In the settings page under "Filter lists", scroll down past the "Built-in" section. You will see sections for "Ads", "Privacy", "Malware", and "Multipurpose". Each section contains additional lists you can enable by clicking the checkbox.
Adding more lists means more things will be blocked, which can sometimes break websites. If you enable extra lists and a site stops working, disable the lists you added and reload the page. You can also create custom rules by clicking the "My filters" tab in settings, but this requires understanding filter syntax and is not necessary for basic use.
For most people, the default configuration is the right balance between blocking and usability. Start with the defaults, and only add more lists if you feel you are still seeing too many ads or tracking requests.
Frequently Asked Questions
Does uBlock Origin work on mobile Chrome?
uBlock Origin is not available for Chrome on Android or iOS. Mobile browsers have different extension systems, and uBlock Origin has not been ported to them. If you want ad blocking on mobile, you can use a different browser like Firefox (which supports extensions on Android) or a DNS-based blocker like NextDNS.
Will uBlock Origin break websites?
Most websites work fine with uBlock Origin enabled. Some sites detect the extension and ask you to disable it or subscribe. A small number of sites may have broken layouts or missing content because the extension blocked something the site needs to function. If this happens, click the shield icon and pause the extension on that site, then reload the page.
Can I use uBlock Origin and another ad blocker at the same time?
You can install multiple ad blockers, but it is not recommended. Running two blockers at once uses more memory, can cause conflicts, and does not block significantly more than one good blocker alone. uBlock Origin is efficient enough that you do not need a second one.
Does uBlock Origin collect data about my browsing?
No. uBlock Origin does not send information about what you visit or what it blocks to any server. The filter lists update from the internet, but the extension does not report back about your activity. You can verify this by reading the source code on GitHub, which is public.
What is the difference between uBlock Origin and uBlock?
uBlock Origin is the original, maintained by Raymond Hill. "uBlock" is a different extension by a different author. uBlock Origin is the one recommended for privacy and security. Always install from the official Chrome Web Store and verify the publisher name is Raymond Hill.