Private IP Addresses (RFC 1918)
You landed here because the IP address you looked up falls inside one of the three private-use ranges defined by RFC 1918. These addresses are reserved for internal networks, are not globally routable, and are reused independently by every home router, office LAN, data center, and cellular carrier on earth. Because they have no single owner and no global uniqueness, there is no authoritative record to look up.
Where you see them
- Home networks. Every consumer router ships with a 192.168.x.0/24 default LAN.
- Enterprise LANs. Large organisations typically subnet out of 10.0.0.0/8 per site and VLAN.
- Kubernetes and Docker. Default pod and bridge networks sit inside 10/8 and 172.16/12.
- VPN concentrators. WireGuard, OpenVPN, Tailscale, and corporate IPsec tunnels hand out RFC 1918 addresses to clients.
- Internal packet captures. If you see 10.x or 192.168.x as a source on a public-facing tcpdump, it is a router leaking its inside interface or a misconfigured NAT.
Frequently asked questions
Can I use 10.0.0.1 on the public internet?
No. RFC 1918 forbids announcing the 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 ranges to the public internet. Every transit provider is expected to drop packets sourced from or destined to these prefixes at its edge. That is why your home router uses 192.168.1.1 but the packets it forwards upstream are NAT-translated to a real, globally routable address.
Why does a 10.x.x.x address have no geolocation?
Geolocation databases are built from BGP routing announcements, WHOIS data, and latency measurements to known network infrastructure. Private IPs never appear in any of those sources because they are never routed on the public internet, are never delegated by an RIR, and every network reuses them independently. There is literally no authoritative record that can map 10.0.0.1 to a country or city.
What devices typically use 192.168.x.x addresses?
Almost every consumer router ships with a default LAN subnet inside 192.168.0.0/16 — common defaults are 192.168.0.1, 192.168.1.1, and 192.168.100.1 depending on the vendor. Corporate networks more often use 10.0.0.0/8 because it gives them 16.7 million addresses to subnet into per-site and per-VLAN blocks.
Will BGP ever announce a 10.0.0.0/8 route?
Not on the public default-free zone. If you see a 10/8 route in a public BGP feed it is either a route leak (someone's iBGP bleeding into their eBGP sessions) or a bogon announcement that transit filters missed. Production networks filter RFC 1918 at every peering boundary.
Is 172.16.0.0/12 the same as 172.0.0.0/8?
No. Only 172.16.0.0 through 172.31.255.255 is private (a /12, which is 1,048,576 addresses). 172.0.0.0 through 172.15.255.255 and 172.32.0.0 through 172.255.255.255 are regular public address space and are delegated to real operators.
Related reading
- Loopback addresses — 127.0.0.0/8 and ::1.
- Link-local addresses — 169.254.0.0/16 and fe80::/10.
- CGNAT addresses — 100.64.0.0/10 (RFC 6598).
- Documentation addresses — RFC 5737 and RFC 3849.
- IPv6 ULA — fc00::/7 (RFC 4193).
- 1.1.1.0/24 (Cloudflare) — example of a publicly routed prefix.