Public vs Private IP Addresses: Find the Right Address

Understand public and private IP addresses, recognise private IPv4 ranges, and work out why your router and an IP checker show different addresses.

WhatsMyIP Team ·

AI-generated illustration of home devices connected to a router and a separate public internet network.

A public IP is the address a website sees for your connection. A private IP identifies a device inside a private network. On a typical home IPv4 network, your laptop and phone have different local addresses but share an internet-facing address. Neither address is a permanent personal identifier.

Need the address visible to this website? Check your public IP address. For a printer or another device on your own Wi-Fi, look for its local address in its network settings instead.

Which address do you need?

Connect to a printer on the same network
Use the printer's local IP. Check that both devices are on the same network; guest Wi-Fi can isolate devices even when they share an internet connection.
Tell a service which internet address to allow
Use the public address seen by that service. A VPN, proxy or a different connection can change it. An IPv4-only allowlist will not cover a separate IPv6 connection.
Reach a home server from outside
A local address alone will not work over the public internet. You also need an appropriate remote-access setup. Start with an authenticated remote-access solution; do not expose a router administration page just to make it reachable.

Recognise the private IPv4 ranges

The three private ranges are defined in RFC 1918. They can be reused by different homes and organisations; they do not identify a unique internet location.

  • 10.0.0.0 through 10.255.255.255 — 10.0.0.0/8
  • 172.16.0.0 through 172.31.255.255 — 172.16.0.0/12
  • 192.168.0.0 through 192.168.255.255 — 192.168.0.0/16

Not every address starting with 172 is private. And “outside these three ranges” does not automatically mean “public”: loopback, link-local, documentation and other special ranges also exist. The IANA special-purpose registry distinguishes them.

Why your router and an IP checker disagree

Read the labels first. A router's LAN address is for the local network; its WAN or internet address is on the upstream side. Comparing a LAN address with a website's result compares two different things.

  1. Check the public IP while connected to the network you want to inspect. Note whether a VPN or proxy is active.
  2. Inspect the router's WAN address without changing its configuration. Compare IPv4 with IPv4, not an IPv4 address with an IPv6 address.
  3. If the WAN address is private, there may be another router or provider NAT upstream. If it falls between 100.64.0.0 and 100.127.255.255, it is in the shared address space reserved for uses such as carrier-grade NAT, not RFC 1918 private space. See RFC 6598.
  4. If incoming connections fail, ask your provider whether it uses shared IPv4 addressing and which inbound options it supports. A port-forward rule on your own router cannot configure a provider's NAT.

For example, a laptop might show 192.168.1.20 and its router 192.168.1.1. Those are illustrative local addresses, not destinations to test on someone else's network. A website normally sees the connection's internet-facing address instead.

Does “private IP” mean private browsing?

No. A private address is an addressing category, not a promise of anonymity or encryption. A VPN can change the public address seen by sites for traffic routed through it, but it does not remove account logins, cookies or every other tracking signal. Our VPN comparison and limitations explains what to check before choosing one.

Addresses containing colons belong to a different family. Continue with IPv4 vs IPv6 rather than applying these IPv4 ranges to IPv6. To investigate an internet-facing address, use IP geolocation; it cannot locate a private device or determine an exact home address.

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