What Is an IP Address? Public vs Private, IPv4 vs IPv6
An IP address is a label that helps connected devices send information to the right place. Phones, laptops, routers, and websites all use IP addresses when they communicate.
An IP address is useful network information, but it is not a personal ID. An address can change, and several people or devices can share one public address. A lookup can provide context about the network, but it cannot identify a person from the address alone.
How does an IP address work?
Imagine that a laptop opens a website over home Wi-Fi. Inside the home, the laptop may use the private address 192.168.1.42. The router connects the home network to the Internet using a public address, represented here by the reserved example address 198.51.100.27. The website normally sees the public address and sends its response there. The router then sends the response back to the laptop.
Laptop ← router ← website
This diagram shows an imaginary home. The address 198.51.100.27 is reserved for documentation and stands in for a public address; it is not a real public Internet endpoint. The laptop's address inside the home and the address seen by the website can be different.
What is the difference between a public and private IP address?
| Type | Where it is used | Example | Visible to a website? |
|---|---|---|---|
| Public | Across the Internet | 8.8.8.8 | Usually yes |
| Private | Inside a home, office, or other local network | 192.168.1.42 | Usually no |
The same private address can be reused in many separate homes and offices because it only needs to be unique inside each local network. A public address is intended for use across the Internet, but it can still be shared by several devices or users. Neither type identifies one person by itself.
What is the difference between IPv4 and IPv6?
IPv4 addresses use four numbers separated by dots, such as 203.0.113.24. IPv6 addresses use numbers and letters separated by colons, such as 2001:db8::1. IPv6 provides far more possible addresses than IPv4.
A device can have an IPv4 address and an IPv6 address at the same time. This is normal and is often called dual stack. The version of an address does not tell you what kind of device it belongs to or who is using it.
What is a static or dynamic IP address?
A static IP address is intended to stay the same. For example, a company may give a server a stable address so people can reach it reliably. A dynamic IP address can change. Home and mobile providers often assign addresses this way.
Static does not mean permanent, and dynamic does not mean the address changes every day. Either type can be public or private. A lookup usually cannot tell how an address was assigned or when it last changed.
What can an IP lookup show?
Open the IP Lens result for 8.8.8.8 for a real example. The details available for other addresses can vary.
A lookup can help show
- Whether the address is public or reserved for a special use
- The organization or network associated with the address
- The address range it belongs to
- An approximate location
- Labels that describe common network uses
A lookup cannot prove
- A person's name or exact street address
- The device or account that made a request
- Whether the traffic was malicious
- Who used the address in the past
- A person's browsing history
Lookup data can be incomplete, and different sources can disagree. Treat the result as useful context rather than proof about a person or event.
Common questions
Why does my device show more than one IP address?
A device can have a private address and use a shared public address. It can also have both IPv4 and IPv6 addresses. Switching between Wi-Fi, mobile service, and a VPN can show still more addresses.
Can someone hack me just because they know my IP?
No. Knowing an address does not give someone access to a device. Safety still depends on secure software and network settings, so keep devices and routers updated.
Can an IP reveal my browsing history?
A public IP lookup does not show browsing history. A website can record activity on its own site, and an Internet provider may keep separate connection records, but those records are not part of an ordinary lookup.