> For the complete documentation index, see [llms.txt](https://www.adblocklabs.com/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.adblocklabs.com/docs/core-concepts/system-level-vs.-browser-ad-blockers-whats-the-difference.md).

# System-level vs. browser ad blockers: what's the difference?

Not all ad blockers do the same job. Both block ads, but as ads get smarter and harder to avoid, browser extensions are hitting their limits. Here's how the two approaches compare, and why system-level blocking is more effective.

## Browser-based ad blockers

These are the most common ad blockers, extensions you install inside a browser like Chrome, Firefox, or Edge. 

They're easy to install, usually free, and fine for casual browsing. But they have real limits:

* They only work in the browser they're installed in, not across your device.
* Modern platforms like YouTube, Facebook, and major news sites increasingly detect and block them.
* Browser changes like Chrome's Manifest V3 restrict what they're allowed to block.
* You have to install and maintain them separately in every browser, on every device.

If you've ever wondered why your ad blocker stopped working on YouTube, this is why.

## System-level ad blockers

AdBlock works differently. Instead of living inside one browser, it installs as a standalone program at the system level and blocks ads across every browser on your PC.

AdBlock runs as a separate program on your computer, not inside a specific browser. That means it blocks ads:

* In every browser you use, be it Chrome, Firefox, Edge or the rest.
* From a single install, with no separate extension to add per browser.
* Consistently, even as browsers change what extensions are allowed to do.

> Think of it this way: a browser extension is a screen on a single window. AdBlock fits every window in the house.

Because it works below the browser, system-level blocking is:

* **More private** — blocks trackers and hidden scripts across all your browsers, not just one.
* **Faster** — ads are stopped before they load, so pages open quicker.
* **Complete** — one install covers every browser, with nothing to add per browser.
* **Durable** — browser changes like Manifest V3 don't affect it.

## Side by side

|                                                | Browser extension                 | System-level (AdBlock)   |
| ---------------------------------------------- | --------------------------------- | ------------------------ |
| Coverage                                       | The one browser it's installed in | Every browser on your PC |
| Separate install per browser                   | Yes                               | No                       |
| Affected by browser updates (e.g. Manifest V3) | Yes                               | No                       |
| Detected or blocked by sites like YouTube      | Often                             | Rarely                   |
| Setup                                          | Per browser, per device           | One install              |


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