this is the comparison nobody asked for but everyone needs. i've been running both adguard and ublock origin in different configurations for the past 2 months, testing which one actually blocks more surveillance and tracking.
the results surprised me.
the test setup
i ran this on a clean firefox installation with a fresh profile. no other extensions, no VPN, no custom DNS. just the blocker being tested.
test methodology:
- visited the same 200 websites across news, e-commerce, social media, and SaaS
- logged all network requests with firefox's devtools
- compared which requests were blocked vs. allowed
- specifically looked for tracking, telemetry, and surveillance-related domains
ublock origin: the open source champion
ublock origin (uBO) is the gold standard for browser ad blocking. it's open source, maintained by raymond hill, and uses community-maintained filter lists.
what it blocked:
- 94.3% of known tracker domains
- 97.1% of advertising domains
- 89.2% of telemetry endpoints
- 78.5% of fingerprinting attempts (with enhanced mode)
strengths:
- completely free, open source, no monetization angle
- dynamic filtering gives granular per-site control
- cosmetic filtering removes ad containers, not just requests
- the community filter lists are extensive and well-maintained
- memory efficient — uses less RAM than any alternative
weaknesses:
- no built-in DNS-level blocking (browser extension only)
- advanced features require manual configuration
- no protection outside the browser
adguard: the commercial alternative
adguard offers both a browser extension and system-wide DNS blocking. for this test, i used the browser extension to make it a fair comparison.
what it blocked:
- 96.1% of known tracker domains
- 98.3% of advertising domains
- 92.7% of telemetry endpoints
- 81.2% of fingerprinting attempts
strengths:
- slightly better out-of-the-box blocking rates
- built-in stealth mode with advanced anti-tracking
- DNS-level blocking available as a separate product
- better cosmetic filtering on some sites
- works across multiple browsers and platforms
weaknesses:
- the free version has limitations
- the full product is paid (about $30/year for 3 devices)
- closed source — you're trusting adguard's code
- some filter lists are proprietary
the head-to-head results
on raw blocking numbers, adguard's browser extension edges out ublock origin by about 2-4% depending on the category. but the difference is small enough that it falls within the margin of different default filter list selections.
the real difference is the ecosystem:
| feature | ublock origin | adguard |
|---|---|---|
| browser extension | free, open source | freemium, closed source |
| DNS blocking | not available | separate product |
| system-wide protection | not available | available (paid) |
| mobile protection | limited | full apps |
| customization | extremely high | moderate |
| maintenance | community | company |
for chat control specifically
here's what matters in the context of chat control: DNS-level blocking is more important than browser blocking.
chat control's surveillance infrastructure doesn't just operate through web browsers. it operates through apps, system services, and background processes. a browser extension like ublock origin can't touch those.
adguard DNS (not the browser extension, the DNS service) blocks tracking and surveillance domains at the network level, protecting every app and service on your device.
my recommendation
use both. seriously.
- ublock origin in your browser — it's free, open source, and excellent
- adguard DNS on your device or router — for system-wide protection
this combination gives you the best of both worlds: ublock's granular browser control and adguard's network-level blocking.
i wrote a detailed comparison with test data and configuration guides: AdGuard vs uBlock Origin — Privacy Comparison
don't choose one when you can have both.
Top comments (1)
The 94-vs-96 gap is real but I think it's measuring the wrong axis. Domain-blocklist hit rate only counts trackers that show up as a distinguishable third-party request, so it's structurally blind to two categories that are actually growing: CNAME-cloaked analytics (served from a subdomain of the site you're on, so it resolves as first-party) and server-side / conversions-API tracking that never touches the browser at all. Since you tested on Firefox, uBO was uncloaking CNAMEs for you via the DNS resolve API — but that same setup on Chromium is blind to them, which is a bigger swing than the 2% headline. And once telemetry moves server-side both tools are 0% by construction. Worth naming so the number doesn't read as "AdGuard catches almost everything."