What Is DNS? The Internet's Phone Book Explained
You type whatismineip.com — but the internet doesn't route by names, it routes by IP addresses. Something has to translate the name into a number before your browser can connect. That something is DNS — the Domain Name System — often called the internet's phone book.
What happens when you visit a website
- Your browser asks a DNS resolver (usually run by your ISP): "What's the IP for this domain?"
- If the resolver doesn't know, it asks the DNS hierarchy: root servers → the registry for
.com→ the domain's own nameservers. - The answer (an IP address) comes back and is cached so the next lookup is instant.
- Your browser connects to that IP and loads the page.
All of this typically takes 10–50 milliseconds — and happens for every domain a page touches, often dozens per page.
Why DNS matters for privacy
Whoever runs your DNS resolver sees every domain you look up — a complete map of your browsing, even for encrypted HTTPS sites. By default that's your ISP. This is also why a misconfigured VPN can suffer a DNS leak: your traffic goes through the tunnel, but your lookups still go to your ISP, quietly revealing your activity.
Popular public DNS resolvers
| Provider | Address | Notable for |
|---|---|---|
| Cloudflare | 1.1.1.1 | Speed, privacy commitment |
8.8.8.8 | Reliability, ubiquity | |
| Quad9 | 9.9.9.9 | Malware-domain blocking |
| OpenDNS | 208.67.222.222 | Content filtering options |
You can change DNS on a single device or network-wide on your router. Modern systems also support encrypted DNS (DNS-over-HTTPS or DNS-over-TLS), which hides your lookups from anyone watching the network.
DNS problems you'll actually meet
- "Server not found" while other sites work — often a stale cache; flushing DNS or switching resolvers fixes it.
- Slow first connection to every site — a sluggish resolver; switching to 1.1.1.1 or 8.8.8.8 often helps.
- Changed a domain's hosting but see the old site — cached records still pointing at the old IP; wait for the TTL to expire.
Related: learn how the reverse process works in reverse DNS lookups, or check what IP your own connection resolves to on our homepage.
Frequently asked questions
Does changing DNS change my IP address?
No. DNS only affects how names are looked up. Your public IP stays the same — verify it anytime on our homepage.
Is 1.1.1.1 or 8.8.8.8 better?
Both are excellent. Cloudflare (1.1.1.1) is often marginally faster and has stronger privacy commitments; Google (8.8.8.8) is extremely reliable. Try each — the difference is usually a few milliseconds.