What DNS is, and why it matters to you
The internet's address book. Whoever answers your lookups has a complete list of where you go.
Updated 2026-09-26
When you type bbc.co.uk, your device does not know where that is. It asks. That question and answer is DNS, and it happens hundreds of times a day without you noticing.
It matters for one reason: whoever answers your questions has a complete list of the sites you visit, in order, with times.
Who answers
By default, your internet provider. Every home router is handed their DNS servers when it connects. So your provider has that list. In the UK, providers also use it to enforce court-ordered blocks, which is why a blocked site "does not exist" rather than refusing to load.
You can change it to someone else — Cloudflare, Google, Quad9 — which moves the list rather than removing it. Pick whoever you would rather have it.
Why it is a privacy problem even with HTTPS
HTTPS encrypts what you send to a site. It does not encrypt the question you asked to find the site. Traditionally that question was sent in plain text, which meant anyone on the network could read it even though they could not read the page.
Encrypted DNS fixes that part. DNS over HTTPS (DoH) and DNS over TLS (DoT) wrap the lookup so only the resolver can read it. Every modern browser and phone supports it and many now default to it. Worth turning on. It hides the question from the network; it does not hide it from whoever answers.
The DNS problems worth knowing
DNS hijacking. Someone controlling your network answers wrongly and sends you to their server instead. This is why a fake Airport_WiFi network is dangerous even though HTTPS exists: they decide where names point, and people click past the warning.
DNS leaks. A VPN that routes your traffic but not your lookups is a VPN that hides your traffic while your provider keeps the list. It is a real and common fault. Ours sends lookups through the tunnel, which is the only sensible way to do it.
What to actually do
- Turn on encrypted DNS in your browser and on your phone. It is usually one switch, and it costs
nothing.
- Do not change your router's DNS to something you found in a forum. A malicious resolver is
worse than your provider.
- If you use a VPN, check it handles DNS. Any VPN that does not is only doing half the job.
What DNS does not do
Changing your resolver does not encrypt your traffic, hide your address, or make you anonymous. It changes who holds one particular list. That is worth doing and it is not the whole picture.
See what the internet sees Free, and it needs no account.