Across seven months and hundreds of daily measurement cycles, one pop network keeps posting numbers we double-checked because we did not believe them: HilltopAds. Out of 3,509 HilltopAds zones our engine tracks, exactly one is currently hard-blocked as confirmed bad supply. That is 0.03% — the cleanest inventory we have ever measured on any pop network.
A correction first: we ranked this differently in April
An earlier version of this article, built on our first-generation engine and a much smaller sample, crowned a different network the cleanest and put HilltopAds mid-pack at 44.6% bot zones. That number did not survive better measurement. Three things changed: the sample grew roughly tenfold; the judge moved to a hard-evidence standard (“can we prove it’s a bot?”, never single weak signals); and we added false-positive recovery that releases zones which later prove human. Under the current engine, seven months of HilltopAds traffic sustains a 93.1% clean rate — and we publish the correction as prominently as the original claim.
The current cross-network picture
- HilltopAds — 0.03% blocked zones, 76 trusted. The cleanest supply we measure, period.
- RollerAds — 7.1% blocked, 117 trusted zones (the most trusted zones of any network). Still an excellent buy, with the best API control we have integrated and the only network where we can measure real render rates end to end. Our earlier praise of RollerAds stands — it was the “cleanest” crown that moved.
- PopAds — 9.3% blocked, with the highest single-zone trust averages on record. See the PopAds correction article.
- Mid-pack networks — 16–44% blocked. Buyable with active zone curation, expensive without it.
- Bottom tier — two networks above 55% blocked zones, including PopCash at 59.6%. Only for aggressive curators.
Why HilltopAds is this clean
We can only measure outcomes, not their internal policies, but the pattern is consistent with strict publisher vetting and active supply policing: bad zones do not merely trickle in slowly — they essentially do not appear. Over seven months the network produced 76 zones that earned our TRUSTED status (sustained high accept rates with real-device, real-behavior evidence), against a single confirmed-bad zone.
The honest caveats
- Clean is not the same as converting. Zone quality removes the bot tax; your offer, creative and bids still decide profit. Test spend discipline applies on clean networks too.
- Exclusion tooling is write-only. HilltopAds’ API accepts blocklist additions but offers no way to read the list back — so verify effects through your own arrival logs rather than assuming.
- Keep filtering anyway. 93.1% clean still means roughly 1 in 15 visits fails checks — and a filter is how you keep proving the 93.1% rather than taking it on faith.
FAQ
Is HilltopAds really the cleanest pop network?
On our current data, yes: 0.03% of 3,509 tracked zones hard-blocked and a 93.1% clean-traffic rate sustained over seven months of continuous measurement — the best figures we have recorded for any pop network.
Didn’t this article previously say RollerAds was cleanest?
Yes — on an early, smaller-sample engine. RollerAds remains excellent (7.1% blocked, the most TRUSTED zones of any network, best API control, measurable render). The ranking changed because the measurement got better, and we corrected it publicly.
Should I still run bot filtering on a clean network?
Yes. A clean network lowers the bot tax; it does not abolish it. Filtering is also your independent evidence — it is exactly how these clean-rate numbers were established in the first place.