ISP Lookup
See which internet provider your connection, or any IP address, belongs to.
How to use the ISP lookup
- Open the page: the tool shows the internet provider of your own connection right away.
- To check another address, enter an IPv4 or IPv6 address and press Find ISP.
- Read the provider name at the top, then the network number (ASN), connection type and location below it.
Where the provider name comes from
Every public IP address belongs to a block that a network operator announces on the internet. That operator has an autonomous system number (ASN) and a registered name, for example "Comcast Cable Communications" or "Deutsche Telekom AG". We look up which network announces the address and show its name, so the result is the company that actually routes the traffic. Read what an ASN is for the details.
Large providers often use several names and networks, and some resell lines from another company. Your bill may show a brand name while the lookup shows the company that runs the network behind it. Both are correct.
What the connection type means
| Type | What it means |
|---|---|
| Residential | A home internet line: cable, DSL or fibre. |
| Mobile network | A mobile operator (4G or 5G). Many users share each address through carrier-grade NAT. |
| Hosting | A data center or cloud company. Servers, VPNs and proxies usually show this type. |
| VPN or proxy | The address belongs to a known VPN, proxy or Tor service, so the real provider is hidden. |
Why the ISP shown is not my provider
- A VPN or proxy is on. Websites see the VPN company, not your provider. Turn the VPN off and reload the page.
- Private Relay or a browser VPN. iCloud Private Relay, Opera VPN and similar features send traffic through another network.
- Your provider rents its network. Smaller providers often use the network of a larger one, and the lookup shows the larger company.
- Mobile data. On mobile data the result is the mobile operator, not your home provider.
More background: how to find out who your ISP is and what CGNAT is.
Frequently asked questions
Can I find a person from their ISP?
No. The ISP name and network only show which company the address belongs to. Only the provider knows which customer used an address at a given time, and it shares that only with the police under a court order.
Is the ISP lookup free?
Yes. There is no sign-up and no limit for normal use.
What is the difference between ISP and ASN?
The ISP is the company. The ASN is the number of the network it runs. One company can operate several ASNs, for example one for home customers and one for mobile.
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