DNS Guides

Run a Speed Test

The Domain Name System is the internet's phonebook — every website visit, email, and app connection starts with a DNS lookup. These guides explain how DNS works at every level, how to choose the fastest and most private DNS server, how to secure your DNS traffic, and how to diagnose and fix DNS failures.

DNS Fundamentals

How DNS Works

The full recursive lookup process — from stub resolver to root nameserver to TLD to authoritative server and back.

DNS Resolver vs Authoritative Nameserver

What each type of DNS server does, why the distinction matters, and how caching sits between them.

DNS Record Types Explained

A, AAAA, CNAME, MX, TXT, NS, SOA, PTR, SRV — what each record does and when you encounter each one.

DNS Propagation Explained

Why DNS changes take time to spread globally, how TTL controls caching, and how to check propagation status.

DNS Servers

Fastest DNS Servers

Benchmark data for Google, Cloudflare, Quad9, OpenDNS, and your ISP's default — and how to measure DNS speed yourself.

Google DNS vs Cloudflare DNS

8.8.8.8 vs 1.1.1.1 — speed, privacy, filtering, and reliability compared side by side.

Public DNS Servers Compared

Every major public DNS resolver — Google, Cloudflare, Quad9, OpenDNS, NextDNS — features and tradeoffs.

How to Change Your DNS Server

Step-by-step instructions for changing DNS on Windows, macOS, Android, iOS, and your router.

DNS Security

What Is DNSSEC?

How DNS Security Extensions use cryptographic signatures to verify that DNS answers have not been tampered with.

What Is DNS over HTTPS?

DoH encrypts DNS queries inside HTTPS traffic — how it works, how to enable it, and what it protects against.

What Is DNS over TLS?

DoT encrypts DNS on a dedicated port — how it compares to DoH and when to use each.

DNS Hijacking Explained

How attackers redirect DNS queries to malicious servers, the types of DNS attacks, and how to protect yourself.

DNS Troubleshooting

DNS Lookup Failed — How to Fix

Step-by-step diagnosis for DNS_PROBE_FINISHED_NXDOMAIN, ERR_NAME_NOT_RESOLVED, and other DNS failure errors.

How to Flush DNS Cache

Commands to clear the DNS cache on Windows, macOS, Linux, Chrome, and Firefox when stale records cause problems.

DNS vs DHCP

Two protocols that both assign address information — what each does, how they interact, and why both matter for your network.