IP Addresses Explained
What is an IP Address?
An IP (Internet Protocol) address is a unique number assigned to every device connected to the internet. It works like a postal address — it tells other computers exactly where to send data. When you open a website or send an email, data is split into small packets and routed across multiple networks using IP addresses as delivery destinations.
IPGu.net displays your public IP address automatically the moment you open the page — the address visible to every website and service you connect to. No action required.
IPv4 vs IPv6
Two versions of IP addressing are in use today:
- IPv4 — four groups of numbers separated by dots, e.g.
203.0.113.1. Supports roughly 4.3 billion addresses. IPv4 space is now exhausted, which is why ISPs use NAT to let many users share a single public IP. - IPv6 — a longer hexadecimal format, e.g.
2001:db8::1. Supports over 340 undecillion addresses, designed to replace IPv4 as devices proliferate with IoT and mobile growth.
Most modern networks support both (dual-stack). IPGu.net shows your IP in whichever format your connection uses at the time.
Public vs Private IP
A device on the internet simultaneously has two types of IP address:
- Public IP — assigned by your ISP and visible on the internet. This is what IPGu.net shows. Every website you visit can see this address.
- Private IP — used only inside your local network (home or office), not directly reachable from the internet. Common ranges:
192.168.x.x,10.x.x.x,172.16–31.x.x.
When you browse from home, your phone and laptop each have a private IP (e.g. 192.168.1.5), but the internet sees only the single public IP of your router. Your private IP never appears on the internet directly.
NAT — why multiple devices share one IP
At home or in an office, every device — phone, laptop, Smart TV — shares the same public IP. That is because your router performs NAT (Network Address Translation), converting the private IP addresses on your local network into a single public IP when sending traffic to the internet. Websites see only that one IP, regardless of how many devices are connected behind it.
NAT also means that geolocation results reflect the router's registered location — not the specific device or room you are in. Every device in your house will show the same IP and the same approximate location on IPGu.net.
Dynamic IP vs Static IP
Most ISPs assign a dynamic IP — one that can change each time you reconnect or when the DHCP lease expires. This is why your IP may change after restarting your router or after a power cut. ISPs use dynamic IPs to allocate the limited pool of IPv4 addresses efficiently across millions of customers.
A static IP stays fixed and must be requested from your ISP, usually at extra cost. Static IPs are mainly useful for hosting servers, remote desktop access, CCTV accessible from the internet, or any system that requires a consistent, permanent address for whitelisting or DNS.
What is IP Geolocation — and how accurate is it?
IP geolocation maps an IP address to an approximate physical location using registration databases — not GPS. This means results are always estimates. IPGu.net uses the MaxMind GeoLite2 database, an industry-standard source updated regularly, but all results remain approximations.
Accuracy varies by level:
- Country level — generally correct (>95% accuracy)
- City level — approximate, can be off by tens of kilometres depending on where the ISP registered the IP block
- Mobile networks — may show the location of the ISP's gateway or regional hub, not your actual city
- VPN or proxy — shows the VPN server's location, not where you physically are
No IP geolocation database can provide a precise street-level address. If a website needs your precise location, it must request browser geolocation permission (which uses GPS or Wi-Fi triangulation, not IP).
What is an ISP?
ISP stands for Internet Service Provider — the company that gives you internet access. Your ISP assigns your public IP address and acts as the gateway connecting your home or office to the global internet. The ISP you are on is registered alongside the IP block in routing databases, which is how IPGu.net identifies it.
Examples in Thailand: True Internet, AIS Fibre, DTAC/NT, 3BB, CAT Telecom. Examples internationally: Comcast (US), Deutsche Telekom (Germany), SoftBank (Japan), BT (UK).
What is an ASN?
An ASN (Autonomous System Number) is a unique identifier for a network operated by one organisation — such as an ISP, university, or large company. Written as AS followed by a number, e.g. AS45758 (True Internet) or AS131445 (AIS).
ASNs are used in BGP (Border Gateway Protocol), the core routing protocol that controls how data moves across the internet. Knowing an ASN tells you exactly which organisation owns the IP address you are looking at. Developers use ASNs to filter cloud provider traffic (AWS, Google, and Cloudflare each have their own ASNs), detect VPN providers, or debug network routing issues.
What are HTTP Request Headers?
Every time your browser loads a web page, it sends HTTP headers alongside the request — metadata that web servers use to understand the client. IPGu.net shows you all the headers your browser is currently sending, which is useful for debugging proxy and CDN configurations without installing additional tools.
Common headers include:
User-Agent— identifies your browser, OS, and version (e.g. "Chrome 120 on Windows 11")Accept-Language— the language preference set in your browser, used for content negotiationX-Forwarded-For— a list of IPs in proxy hop order, used to identify the real client IP behind a proxyCF-Connecting-IP— the real client IP as forwarded by Cloudflare to the origin server
For terminal-based IP commands and header inspection, see the CLI Commands page.
How VPNs, proxies, and Tor affect your IP
Several methods cause websites to see a different IP than your real one:
- VPN (Virtual Private Network) — routes all traffic through a server in another location; websites see the VPN server's IP. Data is encrypted end-to-end. The most widely used approach for both privacy and bypassing regional restrictions.
- Proxy — similar to VPN but typically without encryption, often limited to a single application (e.g. browser only). Faster but offers less protection.
- Tor — routes through multiple anonymous relay layers operated by volunteers for the strongest anonymity, but significantly slower than a VPN. Best suited for high-privacy scenarios, not everyday browsing.
When any of these are active, IPGu.net will show the IP and location of the VPN/proxy/Tor exit node — not your real IP or location.
Frequently Asked Questions
Why does my IP change when I restart my router?
Most ISPs assign dynamic IPs that can change on reconnection. For a fixed IP, request a static IP from your ISP — usually at extra cost.
Can websites know my exact address from my IP?
No. IP geolocation only provides an approximate location (usually city or region), not a street address. For precise location, a website must request permission via the browser's Geolocation API (which uses GPS or Wi-Fi triangulation).
Why does my IP show a different city than where I am?
ISPs register IP blocks at their headquarters or data centres, which may be in a different city than you are. This is especially common on mobile networks, which route traffic through regional ISP hubs.
Can I look up the IP of another website?
IPGu.net only shows your own IP. To look up the IP of a domain, use dig or nslookup in a terminal. See the CLI Commands page for examples.
Does IPGu.net store my IP address?
IPGu.net does not store visitor IP addresses in its own application database. All data is displayed in real time only. Hosting and CDN providers may retain standard access logs per their own policies. See our Privacy Policy.