IP Address Definition
An IP address (Internet Protocol address) is a unique numerical identifier assigned to every device connected to a computer network. It serves two primary functions: identifying the host (or network interface) and providing the location of the device in the network, enabling data to be routed to the correct destination.
Think of an IP address like a postal address for the internet. When you visit a website, your device sends a request that includes your IP address so the server knows where to send the web page data back to.
IPv4 vs IPv6
| Feature | IPv4 | IPv6 |
|---|---|---|
| Address Size | 32 bits | 128 bits |
| Format | Dotted decimal (192.168.1.1) | Hexadecimal (2001:db8::1) |
| Total Addresses | ~4.3 billion | ~340 undecillion |
| Example | 8.8.8.8 | 2001:4860:4860::8888 |
| Status | Running out of space | Virtually unlimited |
| Adoption | Universal | Growing (~40% globally) |
Public vs Private IP Addresses
Public IPs are visible on the internet and assigned by your ISP. Private IPs are used within local networks (home, office) and aren't visible externally. Check your public IP here.
Private IP Address Ranges
| Range | Class | Common Use |
|---|---|---|
| 10.0.0.0 – 10.255.255.255 | A | Large organizations |
| 172.16.0.0 – 172.31.255.255 | B | Medium networks |
| 192.168.0.0 – 192.168.255.255 | C | Home routers |
How IP Addresses Are Used
- Web browsing — Every website you visit sees your IP address.
- Geolocation — IPs can be mapped to approximate physical locations.
- Security — Used for VPN detection, proxy detection, and fraud prevention.
- Networking — Routers use IPs to direct traffic between networks.
- Access control — Servers can allow or block traffic based on IP.
Static vs Dynamic IP Addresses
Static IPs remain constant and are typically used by servers and businesses. Dynamic IPs change periodically and are assigned to most residential connections via DHCP (Dynamic Host Configuration Protocol).
How to Find Your IP Address
The easiest way is to use our What Is My IP tool, which instantly displays your public IP address along with your location, ISP, and security analysis.