What is a public IP address?
A public IP address is the address websites and services see when your device connects to them. At home it usually belongs to your router and is shared by every device behind it; on mobile data or a VPN it belongs to the operator. Your provider assigns it, and it can change.
What the result shows
| Field | What it means |
|---|---|
| Public IPv4 address | The address your traffic comes from, as our server sees it. |
| Reverse DNS | The PTR hostname the address owner set, often naming the ISP and region (for example cpe-203-0-113-7.isp.example). |
| ASN | The autonomous system number of the network that announces the address on the internet. |
| Network / ISP | The organization behind that ASN — your internet provider, mobile operator, VPN or cloud host. |
| Country (approximate) | Where the address is registered or used, from IPinfo's data. It is not your exact location, and no city is shown. |
IP address data is provided by IPinfo Lite under the CC BY-SA 4.0 licence. The page does not store your IP: it is used to answer this request and, hashed, for rate limiting.
Public vs private IP address
Your computer also has a private address, such as 192.168.1.23 or 10.0.0.5, given out by your router. Private ranges are not routed on the internet, so millions of networks reuse them. The router translates between the private addresses inside and its single public address outside (NAT). That is why every device in your home shows the same public IP here.
- Windows:
ipconfigshows the private address; this page shows the public one. - macOS / Linux:
ip addrorifconfigfor private;curl https://ifconfig.cofrom a terminal for public. - Check how big your local network is with the subnet calculator.
IPv4 and IPv6
IPv4 addresses (four numbers, like 203.0.113.7) are running out, so many networks also give devices an IPv6 address (eight groups of hex, like 2001:db8::7). When both work, browsers prefer IPv6. Each IPv6 device usually has its own public address, with no NAT.
Why your IP address changes
- Dynamic addresses. Most home connections get an address leased from the provider that changes after a router restart or every few days.
- Carrier-grade NAT. Many mobile and some fibre providers share one public IPv4 address between many customers (
100.64.0.0/10inside). Port forwarding then cannot work. - VPNs and proxies. With a VPN on, this page shows the VPN server's address and network, not your provider's.
- Static IPs. Businesses that host services usually pay for a fixed address, so DNS records and firewall rules can point at it.
What can someone do with my IP address?
Every website you visit sees it, so it is not a secret. It reveals your provider and an approximate region — not your name or street address; only your provider can link it to an account, normally under a legal order. Exposed services are the real risk: an open router admin page or remote desktop on your public IP is visible to internet-wide scanners within hours. Keep the router updated, close ports you do not use, and prefer a VPN for remote access.
If you run a mail server, the reverse DNS name matters: providers reject mail from IPs without a matching PTR. Check it with the reverse DNS lookup, and test DNS changes with the DNS propagation checker.