Before an app loads anything, it asks for the address. Kuuko DNS answers that question, and for trackers it says “doesn’t exist”.
- An app wants to load something. A news app wants to show an ad from
ads.example.com. First it asks: what is the address of that name? - Your device asks Kuuko, encrypted. The question goes to Kuuko DNS, on two servers, in Germany and Finland. Your Wi-Fi or mobile provider can’t read it. If one server stops answering, your device asks the other; we tested this on 27 October 2026.
- Kuuko checks the block lists. If the name is on a list, Kuuko answers “doesn’t exist” and the ad never loads. Kuuko also checks names that hide behind other names.
It sees. The name your device asks for, and your internet address.
It keeps. No log of lookups. To stop abuse, it holds your internet address in memory for a few minutes, never on disk. Recent answers are kept for everyone, for a day at most, without who asked.
Your choices travel as a short code in the server address, for example k2-103fe. Everyone with the same choices has the same code, so it isn’t an account.
What it can’t do
- Block trackers that use the website’s own name.
- Stop apps that send tracking data to their own company’s servers, the same ones the app needs to work, as Instagram does with Meta.
- Look inside apps or read what they send.
- Tell you what it blocked. It keeps no record, so there is no list to show.
- Answer while a VPN or another app answers DNS on this device. The app checks this and tells you.
To see it work in your browser, use the three tests in Check it yourself.
Block lists: HaGeZi DNS Blocklists, updated every day, and Kuuko’s own lists.
Sources
- Kuuko support page · opened 28 October 2026
- HaGeZi DNS Blocklists · opened 28 October 2026