What Is an IP Address?
An IP (Internet Protocol) address is a unique numerical label assigned to every device connected to a computer network. It serves two primary purposes: identifying the host or network interface and providing the location of the host in the network topology. Every time you load a website, send an email, or stream a video, IP addresses are used to route data between your device and the server.
Understanding IP addresses is fundamental for network administration, security analysis, web development, and debugging connectivity issues. An IP lookup reveals metadata about an address including its geographic location, the organization that owns it, and the Internet Service Provider (ISP) responsible for it.
Public vs Private IP Addresses
Not all IP addresses are visible on the internet. Private IP addresses are used within local networks (like your home Wi-Fi) and are not routable on the public internet. Your router assigns private IPs to each device on your network, while your ISP assigns a single public IP to your router.
# Private IP ranges (RFC 1918)
10.0.0.0 – 10.255.255.255 (10.0.0.0/8)
172.16.0.0 – 172.31.255.255 (172.16.0.0/12)
192.168.0.0 – 192.168.255.255 (192.168.0.0/16)
# Localhost
127.0.0.0 – 127.255.255.255 (127.0.0.0/8)
# Link-local (auto-assigned when DHCP fails)
169.254.0.0 – 169.254.255.255 (169.254.0.0/16)When you perform an IP lookup, you are typically looking up a public IP address. Private IPs cannot be geolocated because they are only meaningful within the context of a local network. Your public IP is what websites and services see when you connect to them.
IPv4 vs IPv6
IPv4 addresses are 32-bit numbers typically written as four decimal-separated octets, like 192.168.1.1. This gives us roughly 4.3 billion possible addresses, which seemed unlimited when the protocol was designed in the 1980s but is now nearly exhausted.
IPv6 was introduced to solve this exhaustion. IPv6 addresses are 128-bit numbers written as eight groups of four hexadecimal digits, separated by colons. This provides approximately 340 undecillion (3.4 x 10^38) possible addresses — enough for every grain of sand on Earth to have its own IP.
# IPv4 example
203.0.113.42
# IPv6 example (full)
2001:0db8:85a3:0000:0000:8a2e:0370:7334
# IPv6 example (shortened)
2001:db8:85a3::8a2e:370:7334
# IPv6 loopback
::1Both IPv4 and IPv6 addresses can be looked up for geolocation data, though IPv6 adoption is still growing. Most IP lookup services support both versions.
IP Geolocation
IP geolocation is the process of mapping an IP address to a physical location. Geolocation databases maintain records that associate IP address ranges with countries, regions, cities, and sometimes postal codes. The accuracy varies: country-level detection is typically over 99% accurate, while city-level detection ranges from 50% to 80% depending on the database and the ISP.
Geolocation data typically includes the country, region or state, city, latitude and longitude, timezone, and the Autonomous System Number (ASN) of the network. This information is derived from Regional Internet Registry (RIR) records, ISP data, and statistical inference from network routing.
Common Use Cases
Security and Fraud Detection
IP lookups are a core component of fraud detection systems. If a user logs in from a country they have never accessed before, or if the IP belongs to a known VPN or proxy service, security systems can flag the activity for review. Comparing the IP location against the billing address helps detect unauthorized access.
Analytics and Content Localization
Web analytics platforms use IP geolocation to segment visitors by country and region. This data drives decisions about content localization, ad targeting, and market expansion. E-commerce sites use it to display prices in the local currency and suggest relevant shipping options.
Network Troubleshooting
When debugging connectivity issues, looking up IP addresses helps identify where traffic is being routed. You can determine whether an IP belongs to a CDN, a cloud provider, or an end-user ISP. This context is invaluable for diagnosing latency, routing problems, and DNS misconfigurations.
How to Use the IP Lookup Tool
Open the IP Lookup tool and follow these steps:
- View your public IP — the tool automatically detects and displays your current public IP address.
- Enter any IP address to look up its geolocation, ISP, organization, and timezone information.
- Review the results — the tool displays country, region, city, coordinates, timezone, and network details.
- Check multiple IPs to compare locations or investigate suspicious addresses from your logs.
The tool supports both IPv4 and IPv6 addresses. It is free to use and provides accurate geolocation data for any publicly routable IP address.
Ready to look up an IP? Open IP Lookup