ipaddress.nl answers questions about IP addresses and networks: from “what is my IP address” to “which autonomous system announces this range and which registry is it registered with”. Fast, in Dutch first, and without having to create anything.
We show facts and say where they come from
Every figure on this site traces back to a public source: the global routing table, the delegated files of the five regional registries, IANA's RDAP bootstrap, or a live DNS or RDAP answer. The Data sources page lists them by URL, with the date we last read each one.
Where we do not know, we say so
There is no city next to an address when we cannot establish one reliably, and no VPN verdict when we cannot support it. “Not available” is a better answer than an estimate presented as a fact — and it is the answer most competitors will not give you.
No third-party API in the critical path
Routing, registration and AS-name data are compiled periodically into binary indexes on our own disk. A lookup is therefore one binary search in memory rather than a network request to somebody else. That is why the site is fast, and why your query does not end up with a third party.
Sister projects
ipaddress.nl shares its architecture with ipaddress.jp and ipaddress.im. The same precision, worked out per market.