Anycast IP Addresses Explained

Quick answer: Anycast allows the same IP address to be announced from multiple network locations so traffic can be directed toward a suitable route.

Why websites use anycast

Anycast can improve resilience and reduce latency by allowing traffic to enter a service through different network locations. DNS providers, CDNs and other globally distributed services commonly use this design.

Why location tools can look surprising

An anycast address can represent a distributed service rather than one physical server. That is one reason an IP geolocation result should be treated as an estimate rather than a GPS reading.