Guides
26 explanations of addresses, routers, DNS and leaks. Each one answers the question in its first paragraph, cites the RFC or the vendor page behind the claim, and carries the date it was last checked. No fear-bait, and no padding to reach a word count.
Addressing basics
What an address is, which ranges mean what, and why yours changes without warning.
- Public vs private IP addresses/guides/public-vs-private-ip
A public IP identifies your network on the internet. A private IP identifies a device inside it. RFC 1918 ranges, CGNAT space, loopback and link-local.
- IPv4 vs IPv6/guides/ipv4-vs-ipv6
IPv4 is 32-bit and nearly exhausted. IPv6 is 128-bit and needs no NAT. The differences that matter, plus current adoption numbers from Google.
- Static vs dynamic IP addresses/guides/static-vs-dynamic
A dynamic IP comes from a DHCP lease and can change. A static IP never does. How ISPs actually assign addresses, when you need a static one, and when DDNS is enough.
- What your IP address reveals/guides/what-an-ip-reveals
An IP address gives away your ISP, your ASN, and an approximate city. It does not give away your name, your street, or access to your devices. Here is the line.
Find your IP
The exact menu path and the exact command, per platform, checked against current releases.
- Find your IP address on Windows/guides/find-ip-windows
Three ways to read your local IP on Windows 11: the Network & internet settings page, ipconfig in a terminal, and Get-NetIPAddress in PowerShell.
- Find your IP address on a Mac/guides/find-ip-mac
Read your Mac's local IP in System Settings under Wi-Fi Details, or run ipconfig getifaddr en0 in Terminal. Plus the fast Option-click trick and the public IP.
- Find your IP address on Linux/guides/find-ip-linux
ip -br a for a readable list, hostname -I for a quick answer, nmcli for NetworkManager detail, and curl whatsmyip.fyi for the public address.
- Find your IP address on iPhone/guides/find-ip-iphone
Find the private Wi-Fi IP in Settings under the (i) button, find the public IP by opening whatsmyip.fyi, and see why iOS hides the cellular address.
- Find your IP address on Android/guides/find-ip-android
Two paths that work on every Android: the network details screen under Wi-Fi, and the IP address row in About phone. Plus the public IP and mobile data.
- Find your router's IP address/guides/find-router-ip
Your router's address is your default gateway. One command per platform: ipconfig, ip route, netstat -nr, route -n get default, plus the iOS and Android screens.
Home network and routers
Gateway addresses, admin pages, carrier-grade NAT, and the reasons a login page refuses to load.
- 192.168.1.1/192-168-1-1
192.168.1.1 is a private address most routers use for their admin page. How to sign in, which brands ship it, and what to do when the page will not load.
- 192.168.0.1/192-168-0-1
192.168.0.1 is the default admin address on D-Link, TP-Link and many cable gateways. Login steps, the difference from 192.168.1.1, and troubleshooting.
- 10.0.0.1/10-0-0-1
10.0.0.1 is the admin address on Comcast Xfinity gateways and a common gateway on business networks. What the 10.0.0.0/8 range is for, and how to sign in.
- 192.168.1.254/192-168-1-254
192.168.1.254 is the admin address on BT Smart Hubs, Technicolor and Arris gateways, and AT&T equipment. Why ISPs pick .254, how to sign in, and fixes.
- Carrier-grade NAT (CGNAT)/guides/cgnat
Carrier-grade NAT puts your router behind a shared ISP address from 100.64.0.0/10. How to detect it, what it breaks, and how to ask for a public IP.
- Port forwarding/guides/port-forwarding
A port forward tells your router where to send an unsolicited inbound connection. Setup, static leases, UPnP, CGNAT as the usual blocker, and the security rules.
Privacy and exposure
What an address actually discloses, how to replace it, and how to check that the replacement holds.
- How to hide your IP address/guides/hide-my-ip
VPN, Tor, proxy, or a different network. What each one actually hides, what it does not, and how to verify the result instead of trusting a marketing claim.
- How to change your IP address/guides/change-ip-address
Release and renew the DHCP lease, power the modem down long enough for the lease to expire, clone a new MAC, or route through a VPN. What works per platform.
- Can someone find my location from my IP address?/guides/can-someone-find-me-with-my-ip
An IP resolves to a city or region, often the wrong one. Your street address sits only with your ISP, released under legal process. What the databases hold.
- Why a site thinks you are somewhere else/guides/why-does-a-site-think-im-somewhere-else
IP geolocation is inferred, not measured. Stale database entries, distant ISP gateways, anycast, VPN egress, and mobile carriers, plus where to file a correction.
- WebRTC leaks/guides/webrtc-leaks
WebRTC gathers host, server-reflexive, and relay candidates to set up peer connections. What each one reveals, why mDNS fixed most of it, and per-browser settings.
DNS
How name resolution works, who answers for you, and what a leak test can and cannot prove.
- What is DNS?/guides/dns-explained
DNS turns names into addresses through a resolver that walks the root, TLD, and authoritative servers. Record types, TTL, and what DoH and DoT change.
- How DNS leak tests work/guides/how-dns-leak-tests-work
A DNS leak test uses unique random subdomains under a domain it controls, then reports the source IP of every resolver that asked. Here is the whole mechanism.
For developers
Scripting the address, reading an ASN, and interpreting an IPv6 result rather than trusting a badge.
- Get your public IP from a script/guides/get-public-ip-from-script
One endpoint, five languages. curl https://whatsmyip.fyi/ip returns the address as plain text. JSON field reference, rate limits, timeouts, and retry rules.
- How the IPv6 test works/guides/ipv6-test-explained
Why one hostname cannot test both families, what the v4-only and v6-only probes prove, how RFC 8305 decides the winner, and how to reproduce the whole thing with curl.
- What is an ASN?/guides/what-is-an-asn
An ASN identifies one network that announces its own routes in BGP. 16-bit and 32-bit numbering, the private ranges from RFC 6996, the RIRs, and how to read one.