Piholekiller vs CanYouBlockIt
CanYouBlockIt tests your ad blocker against real publisher sites — nytimes.com, forbes.com, cnn.com and others — and reports what got through. Piholekiller runs a synthetic 103-probe gauntlet with reproducible category scores. Both tools are legitimate. The right choice depends on whether you want the real-world outcome or the reproducible baseline.
The difference in one line: CanYouBlockIt loads ~10 real publisher sites (nytimes.com, forbes.com, cnn.com) and reports what your blocker let through in the real world — an intuitive result that drifts as publishers change their ad tech. Piholekiller runs a fixed 103-probe synthetic gauntlet with per-category scores that stay stable across weeks, so two blockers are directly comparable and regressions are traceable. Use CanYouBlockIt for the real-world outcome, Piholekiller for the reproducible benchmark.
Summary comparison
| Dimension | CanYouBlockIt | Piholekiller |
|---|---|---|
| Test type | Real publisher sites | Synthetic 103-probe gauntlet |
| Reproducibility | Varies (publishers change configs) | Stable across weeks |
| Test count | ~10 publisher sites | 103 categorized probes |
| Category breakdown | Totals only | Per-category scores |
| DoH bypass detection | No | Yes |
| Fingerprinting probes | Partial | Explicit category |
| Leaderboard | No | Yes (public scoreboard) |
| Best for | "How does my blocker handle real sites?" | "Reproducible blocker benchmark" |
What does CanYouBlockIt do well?
CanYouBlockIt is the most directly intuitive ad-blocker test. It loads real publisher sites in an iframe, records the network requests, and reports how many were blocked. If your blocker stops every request on nytimes.com, that is exactly what the test reports — and it is exactly what you would experience visiting the site yourself. The mental model is clean: real blocker, real site, real result.
The test has been the go-to reference in the ad-blocker community for years because the results are trivially believable. There is no abstraction layer, no interpretation step. You either saw fewer ads on The New York Times or you did not.
Where the real-site approach gets tricky
The limitation of real-site testing is that publishers change their ad tech constantly. A result from last Tuesday reflects the ad-tech configuration The New York Times had deployed last Tuesday — which may differ from today by a dozen new vendors, a different header-bidding wrapper, a rotated SSP, or a migration from GAM to a different supply-side platform. Last week's "my blocker catches 87% of requests" reading may be this week's 91% or 73%, not because your blocker changed but because the publisher did.
This drift is not a flaw in CanYouBlockIt's methodology. It is a consequence of measuring a moving target. For a one-shot "how is my blocker doing today" answer, this is fine. For comparing two blockers or tracking your own configuration over time, publisher drift introduces noise that can easily exceed the signal you are trying to measure.
Why is Piholekiller synthetic on purpose?
Piholekiller's gauntlet is 103 static test probes organized into categories: display ads, video ads, tracking pixels, fingerprinting scripts, DNS-over-HTTPS bypass attempts, telemetry beacons, malware hosts, and popunder triggers. The probes do not change between runs. A perfect blocker in April will also be a perfect blocker in December against the same gauntlet — which means a regression between those runs points to a real change in blocker coverage, not a shift in the test environment.
The reproducibility matters for three use cases. First, comparing two blockers side-by-side: synthetic scores are directly comparable; real-site scores are not. Second, tracking your own Pi-Hole blocklist updates: a drop in category score after a blocklist change tells you exactly which category regressed. Third, publishing scoreboards: the Piholekiller leaderboard ranks blockers by synthetic score across thousands of submissions, and the ranking is stable because the underlying test is stable.
Which should you use?
- "Does my blocker work on the sites I actually read?" — CanYouBlockIt. Real sites.
- "Which of these two blockers is stronger overall?" — Piholekiller. Reproducible synthetic comparison.
- "Is my blocklist catching DNS-over-HTTPS bypass?" — Piholekiller. Explicit DoH category.
- "Has my Pi-Hole configuration regressed since last month?" — Piholekiller. Scores are comparable across time.
- "I just want a satisfying 'ads got stopped' confirmation" — CanYouBlockIt. Real-site intuitiveness wins.
Should I run both CanYouBlockIt and Piholekiller?
Run CanYouBlockIt first to confirm your blocker handles the publishers you actually visit. Run Piholekiller second for the reproducible per-category benchmark that is stable across weeks and comparable between configurations. The real-site validation plus the synthetic baseline together form a complete picture of blocker coverage that neither provides alone.
Frequently asked questions
- What is CanYouBlockIt?
- A free ad-blocker test that loads real publisher sites and reports how many trackers and ads were blocked.
- Is CanYouBlockIt accurate?
- Yes, within its methodology. Results reflect your blocker's behavior against the specific sites tested on the day you run it.
- How is Piholekiller different?
- Piholekiller runs a synthetic 103-probe gauntlet with reproducible category scores instead of real-site observations.
- Which score is more meaningful?
- Real-site for day-to-day browsing experience, synthetic for scientific comparison.
- Should I run both?
- Yes. Real-site validation plus synthetic baseline is the most complete picture.