WHOIS: How to Check Domain Information
22 Feb 2026
What Is an IP Address
An IP address (Internet Protocol Address) is a unique numerical identifier assigned to every device connected to a computer network that uses the IP protocol for data transmission. Put simply, an IP address is your digital address on the internet, similar to a postal address in the physical world.
Every time you open a website, send an email, or download a file, your device uses its IP address for identification and data exchange. Without IP addresses, the internet as we know it simply could not function at all.
An IP address serves two primary functions: identifying a host (or network interface) and addressing its location within the network. These two functions allow routers to find the optimal path for delivering data packets from sender to receiver across dozens or even hundreds of intermediate nodes.
IPv4 vs IPv6: Two Generations of Addresses
IPv4
IPv4 is the fourth version of the IP protocol, developed in 1981. An IPv4 address consists of four octets (number blocks) separated by periods, for example: 192.168.1.1. Each octet can contain a value from 0 to 255, giving a total of approximately 4.3 billion unique addresses (2 to the power of 32).
While 4.3 billion may seem like a lot, with the growth of the Internet of Things (IoT), mobile devices, and global digitization, it is no longer enough. The pool of free IPv4 addresses was officially exhausted in 2019, and today new addresses are distributed only through the secondary market, where a single address can cost 50β60 dollars.
IPv6
IPv6 is the next generation of the protocol, using 128-bit addressing. An IPv6 address appears as eight groups of four hexadecimal digits separated by colons, for example: 2001:0db8:85a3:0000:0000:8a2e:0370:7334. The number of possible IPv6 addresses is 340 undecillion (3.4 times 10 to the power of 38), which is enough to assign an address to every atom on the surface of the Earth.
Beyond the larger address space, IPv6 offers built-in IPsec support for encryption, simplified routing, and device auto-configuration. However, the transition to IPv6 has been gradual β as of 2026, only about 45% of global internet traffic uses IPv6. The main reason for the delay is the enormous amount of equipment and software that needs to be updated.
Public vs Private IP Address
Public IP Address
A public (external) IP address is the address that the entire internet can see. It is assigned to your router by your Internet Service Provider (ISP) and serves as your "calling card" on the network. All devices on your home network share a single public IP address through a mechanism called NAT (Network Address Translation).
Want to find out your public IP address? Use our My IP Address tool β it will show your external IP address, provider, approximate location, and other technical details about your connection instantly and for free.
Private IP Address
A private (internal) IP address is used within a local area network (LAN). Your router, computer, smartphone, and printer each receive a unique private IP address. Private address ranges are defined by the RFC 1918 standard:
- 10.0.0.0 β 10.255.255.255 (Class A, 16 million addresses) β used by large organizations
- 172.16.0.0 β 172.31.255.255 (Class B, 1 million addresses) β medium networks and VPNs
- 192.168.0.0 β 192.168.255.255 (Class C, 65,536 addresses) β home routers and small businesses
Private addresses are not routed on the internet β they only work within the boundaries of your local network. The same 192.168.1.x range can be used by millions of home networks simultaneously without creating any conflicts.
How IP Addressing Works
DNS β Domain Name System
When you type "google.com" into your browser, a DNS query occurs that converts the domain name into an IP address (for example, 142.250.185.238). This process is called DNS resolution and happens in milliseconds, completely transparent to the user. Without DNS, we would have to memorize numerical addresses for every website, which would be practically impossible.
DNS operates on a hierarchical model. First, the query goes to your ISP's recursive DNS resolver, then to a root DNS server, then to the domain zone server (.com, .ua, etc.), and finally to the authoritative DNS server for the specific domain. Results are cached at each level to speed up subsequent queries.
DHCP β Automatic Address Assignment
DHCP (Dynamic Host Configuration Protocol) is a protocol that automatically assigns IP addresses to devices on a network. When you connect your laptop to Wi-Fi, the DHCP server (usually built into the router) automatically provides your device with an IP address, subnet mask, default gateway, and DNS server addresses. This happens through a process of "leasing" an address for a specific period of time.
Static vs Dynamic IP Address
A static IP is a fixed address that does not change upon reconnection. It is used for servers, network printers, and devices that need constant accessibility. A dynamic IP is an address that may change with each connection or at certain time intervals. Most home users have a dynamic IP address, which makes tracking them more difficult but makes hosting servers impossible without additional services.
NAT β Network Address Translation
NAT (Network Address Translation) is a technology that allows multiple devices on a local network to share a single public IP address. When your computer (192.168.1.100) sends a request to a website, the router replaces the private address with the public one and remembers the association. When the response comes back, the router knows which device to forward it to. NAT has become a critically important technology given the shortage of IPv4 addresses.
IP Address Geolocation
IP geolocation is the determination of the approximate geographic location of a device based on its IP address. Accuracy depends on the database and IP type: for fixed-line connections, accuracy is typically at the city level, while for mobile connections, it is at the regional level. Geolocation never provides an exact address β only an approximate area.
IP geolocation is used to display relevant content (language, currency, local news), targeted advertising, fraud prevention, and enforcement of regional restrictions (geo-blocking). Streaming services like Netflix use IP geolocation to determine which content to show in your region based on licensing agreements.
Find out what can be determined from your IP address using our IP Lookup tool. You will see the country, city, provider, ASN, and other technical details for any IP address in the world.
VPN and IP Address Privacy
What Is a VPN
A VPN (Virtual Private Network) is a technology that creates an encrypted tunnel between your device and a VPN server. All your internet traffic passes through this tunnel, and websites see the VPN server's IP address rather than your real address. This allows you to hide your location and encrypt your data from outside observers.
Why Hide Your IP Address
- Privacy: your ISP and advertisers cannot track your online activity or build a profile of your interests
- Security on public Wi-Fi: VPN protects your data from interception in cafes, airports, and hotels where networks are often unsecured
- Bypassing geo-restrictions: access content restricted in your region β streaming services, games, and news websites
- Preventing DDoS attacks: relevant for gamers and streamers who may be targeted by their IP address
- Bypassing censorship: in some countries, a VPN allows access to blocked websites and services
Does VPN Provide Complete Anonymity
A VPN hides your IP address but does not provide complete anonymity. Cookies, browser fingerprinting, and logging into Google or Facebook accounts can all identify you even through a VPN. For maximum privacy, combine a VPN with incognito mode and tracker-blocking extensions. Also consider that free VPN services may collect and sell your data, so choose trusted providers with clear privacy policies.
Security and Threats Related to IP Addresses
What Can an Attacker Do with Your IP
Knowing an IP address alone does not provide direct access to your device. However, an attacker can determine your approximate location, attempt a DDoS attack (flooding your router with traffic), search for router vulnerabilities, or use the IP for targeted phishing campaigns. Therefore, do not post your IP address on forums or social media.
How to Protect Your IP Address
- Use a VPN or proxy server to mask your real IP address during everyday browsing
- Update your router firmware regularly and change default administrator passwords
- Enable the firewall on both your router and your operating system to block unwanted connections
- Do not click suspicious links β they may be designed to log your IP address through tracking pixels
- Use DNS servers with encryption support (DNS over HTTPS or DNS over TLS)
Useful Tools for Working with IP Addresses
For checking and analyzing IP addresses, use our free tools:
- My IP Address β instantly find your public IP address, provider, and approximate location
- IP Lookup β detailed information about any IP address: geolocation, ISP, ASN, connection type
Conclusion
An IP address is a fundamental element of the internet that enables communication between billions of devices worldwide. Understanding the principles of IP addressing helps you better navigate network security, privacy, and troubleshooting connectivity issues. Check your IP address right now using our free tool and discover what the internet knows about you.
