Guides
Short explainers that go with our free lookup tools—written to help you understand the result, not just read a number.
Public vs private IP addresses
Learn the difference between public and private IP addresses, why both exist, NAT, and which one websites can see.
IPv4 vs IPv6
Clear explanation of IPv4 and IPv6, dual-stack networks, NAT, and why a checker might show one or both addresses.
Why IP location can be wrong
Understand IP geolocation limits: why city or region can be off, how databases work, VPNs, and what IP location is not.
What websites see about your connection
A practical rundown of public IP, headers, user agent, language, and what a VPN changes—without scare tactics.
Understanding ASN and ISP lookups
How autonomous system numbers relate to your internet provider, why names look unfamiliar, and how to read our network tools.
DNS blacklists explained
What DNS-based block lists mean for your IP, why listings happen, and how to interpret our blacklist check.
Browser fingerprinting basics
What canvas and WebGL signals are, how they differ from cookies, and how to read our educational fingerprint tools.
Screen resolution vs viewport
The difference between screen size, CSS pixels, device pixel ratio, and the browser viewport—for layout and debugging.
Timezone, UTC, and Unix time
How local time, UTC, offsets, daylight saving, and Unix timestamps relate—and which tool to use for each.
How we detect your IP address
Technical overview of server-side IP detection, dual-stack probes, headers, and limits of what an IP checker can know.
Why we publish guides
Lookup tools answer “what is my …?” in a second. Guides answer “what does that mean?” so the site stays useful for learning and troubleshooting, not only for a one-line result.