What we store: nothing on disk. While a test runs, our server holds your public IP address, its network owner and approximate location, and the IP addresses of the DNS resolvers that answered, in memory only. Each test is deleted about 10 minutes after it starts (our server clears expired tests every 30 seconds), or as soon as our server receives your cancel. We don't link this to a name, email or account, we don't sell it, and we don't use it for advertising.
What we store
| What | Why | Kept for |
|---|---|---|
| Your public IP address | To show it to you and compare its network with your resolvers | Up to 10 minutes, in memory |
| Network owner and location of that IP | Looked up from offline registry and geolocation data to explain the result | Up to 10 minutes, in memory |
| Resolver IP addresses | They are the test result | Up to 10 minutes, in memory |
| Test names your browser looked up | Random, single-use names that link answers to one test | Up to 10 minutes, in memory |
| Request counts per IP address | Rate limits that stop the test server being abused | In memory, until 5 minutes after your last request |
| Sites you visit | We never see them. The test only uses names on our own domain. | Not collected |
Our test server doesn't write IP addresses to its logs, and it is set up so a crash can't save its memory to disk.
During the test
Your browser loads a few random addresses on our domain. Your DNS resolver asks our server for them, which is how we learn the resolver's IP address. Copy result puts the summary on your own clipboard. Nothing is published or shared by us.
Where the network data comes from
Network owners come from the public iptoasn.com data. Approximate locations come from IP Geolocation by DB-IP, used under the Creative Commons Attribution 4.0 licence. Both are files on our own server, so your IP address is never sent to them.
Hosting and analytics
Cloudflare hosts these pages and sits in front of our test API, so it also sees your IP address when you load a page or run a test, under its own privacy policy and retention. Our test server, which answers the DNS lookups and runs the test API, is a machine we rent from UpCloud in the United States. We count visits with Umami, an analytics tool we host ourselves. It sets no cookies and does not store IP addresses. Visit counts are kept for up to 24 months, because we have a legitimate interest in knowing how the site is used.
Cookies and advertising
We show ads from Google AdSense to keep the test free. Third-party vendors, including Google, use cookies to serve ads based on your previous visits to this and other websites. You can turn off personalised advertising in Google's Ads Settings. In the UK, EEA and Switzerland, ad cookies are set only after you agree in the consent banner from Google’s Privacy & messaging tool, a Google-certified consent platform, and you can change that any time from Cookie settings.
We also store one small preference in your browser: your light or dark theme choice. It is not a tracking cookie and never leaves your device.
Affiliate links
Links to VPN services may be affiliate links. Our applications are pending, so none are live yet. Once they are, clicking one lets that service set a cookie to record the referral. We never pass your IP address or test result to them. See the affiliate disclosure.
Your rights
Under the GDPR, UK GDPR and similar laws you can ask what we hold about your IP address. Because test data is deleted within 10 minutes and never written to disk, there is usually nothing left by the time a request reaches us. Our legal basis is legitimate interest in running the test and preventing abuse. For ad cookies it is your consent. You can complain to your local data protection authority.
Contact
DNS Leak Scan (dnsleakscan.com) is run by DEV2REV, Porto, Portugal. We are the data controller for the limited data described here. Email hello@dnsleakscan.com or use the contact page.