Privacy and IP basics
Private, Reserved, and Special IP Addresses: What They Mean
Addresses such as 10.0.0.1, 192.168.1.1 and 127.0.0.1 are private, loopback or reserved. What each range is for and why a public lookup returns nothing for them.
- Author
- Mojahid Ul Haque
- Updated
- Reading time
- 2 min read
Private addresses
Private IP ranges are used inside local networks and are not routed on the public internet. Common examples include 10.0.0.0/8 and 192.168.0.0/16.
Many homes and offices reuse the same private ranges because they are only meaningful inside each local network.
Special-use addresses
Some IP ranges are reserved for loopback, link-local, benchmarking, documentation, multicast, and other special purposes.
| Range | Purpose | What a public lookup returns |
|---|---|---|
| 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 | Private networks (RFC 1918) | Nothing: never routed on the internet |
| 100.64.0.0/10 | Shared address space for carrier-grade NAT (RFC 6598) | Nothing: lives between the subscriber and the ISP |
| 127.0.0.0/8 and ::1 | Loopback: the device talking to itself | Nothing |
| 169.254.0.0/16 and fe80::/10 | Link-local: a single network segment, often when DHCP failed | Nothing |
| 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24, 2001:db8::/32 | Documentation and examples | Nothing: reserved so examples never hit a real host |
| fc00::/7 | IPv6 unique local addresses (the IPv6 counterpart of private ranges) | Nothing |
| 224.0.0.0/4 and ff00::/8 | Multicast | Nothing: not a single host |
| 0.0.0.0/8, 240.0.0.0/4, 255.255.255.255 | "This network", reserved, limited broadcast | Nothing |
These addresses usually should not be treated like ordinary public visitor IPs in fraud, geolocation, or analytics systems.
How tools should handle them
A good IP lookup tool validates the address and explains when the IP is private or special-use instead of pretending it has a normal public location.
For public geolocation, check the public IP that websites see, not the private address assigned inside your Wi-Fi or LAN.
Frequently asked questions
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