How IP address lookup works
Every public IP address belongs to a block that a regional registry (ARIN, RIPE, APNIC, LACNIC or AFRINIC) has allocated to an organisation — usually an internet provider, a hosting company or a large enterprise. That allocation is public, which is why the ISP and autonomous system (ASN) for any address can be identified with near-perfect accuracy.
Location is different. Nothing in the IP itself encodes a place. Geolocation providers infer it by combining the registry's contact address, how the block is routed, latency measurements from many vantage points, and sometimes data that websites share back. This lookup uses the DB-IP database (refreshed monthly) with ipinfo.io as a fallback, and resolves the reverse DNS hostname live.
What you get for any IP
- Country, region, city and approximate coordinates on a map
- ISP / organisation and ASN that announces the address
- Hostname (reverse DNS), which often reveals the network type — e.g.
dsl,cable,mobile, or a hosting provider - Timezone and continent
- Whether the address is private (10.x, 172.16–31.x, 192.168.x) and therefore not routable on the internet
How accurate is it?
- Country: correct for roughly 99% of addresses
- City: typically within 25–50 km for fixed broadband; often the regional gateway city for mobile carriers
- Coordinates: the centre of the estimated city — never a street address
- VPN / proxy / data-centre IPs: location reflects the server, not the person using it
Common reasons to look up an IP
- Check a suspicious login or email. Paste the address from the security alert or from our email header analyzer to see which network and country it came from.
- Verify your VPN. Look up your own address while connected; the country and ISP should be the VPN provider's, not your home ISP's. Then run the leak test for WebRTC and DNS.
- Investigate server logs or abuse reports. Identify the hosting provider behind scraping or brute-force traffic, then use the reverse IP lookup to see what else is hosted there.
- Debug geo-restrictions. If a service says you are in the wrong country, the lookup shows what its geolocation provider most likely sees.
- Build it into your app. The IP geolocation API returns the same fields as JSON with a generous free tier.
Frequently asked questions
Can I find someone's exact address from their IP?
No. IP geolocation resolves to a city at best. Only the ISP holding the subscriber records can link an address to a person, and it will only do so under legal process.
Why does my own IP show a city 100 km away?
Your ISP routes your traffic through a regional hub and registered the address block there. Mobile networks are the most common cause; the database is reporting where the carrier's gateway is, not where your phone is.
Does the lookup work with IPv6?
Yes. Enter any IPv6 address (for example 2001:4860:4860::8888) and you get the same fields. Note that IPv6 geolocation is generally less precise than IPv4.
What does "hostname" tell me?
It is the reverse DNS (PTR) record the network owner set for that address. Residential ISPs often encode the connection type and region; hosting providers usually show their brand; many addresses have none at all.
Do you log the addresses I look up?
Requests go through our server and appear in short-lived access logs like any web request. We do not build profiles or sell lookup data. See the privacy policy.