Agreement is evidence. Not a guarantee.

Sextant looks up the most detailed free city databases from three independent providers, locally. It selects the most common country, then region within that country, then city within that region. Missing fields abstain; mirrors never count as extra votes. A tie prefers the more detailed record, then a reported accuracy radius, then GeoLite2, IP2Location, and DB-IP. A selected coordinate is an actual provider point, never an average between cities.

All provider points are shown, including disagreements. One dotted circle encloses every available point, showing how far the providers' locations differ, with a little visual padding. A single point or coincident points get a small ring. Precision (spread) is the great-circle distance in kilometres from the selected location to the farthest available provider point. It is zero for coincident points and unavailable when the selected location has no coordinates. Neither value is measured accuracy or a statistical confidence bound; agreement does not guarantee correctness. IP geolocation cannot locate an individual, household, or device precisely. Anycast, VPNs, and mobile networks can produce particularly misleading locations.

Anycast detection uses only locally cached IPv4 and IPv6 exports from Manycast / the LACeS Anycast Census. A prefix needs AB > 3 or GCD > 1; low-confidence detections are ignored. Confidently anycast addresses show a world map without location markers or a spread circle. Provider locations are hidden in the interface but remain in the API response for inspection. Missing detection or unavailable census data does not prove an address is unicast; check database freshness for availability and update errors.

Databases are checked daily, with last-known-good data retained on update failures. GeoLite2 files older than 30 days are excluded. Map tiles are loaded from OpenStreetMap; viewing the map sends your browser's IP and tile requests to that service. Lookups stay local by default. Enabling External APIs sends the searched IP from this server to IPLocate and ip-api for live results, which join the map and place/ASN votes. These services may share underlying data with other providers, so they are not necessarily independent evidence. External failures do not discard available local results. Your hosting administrator may retain HTTP access logs.

Data distributions: sapics/ip-location-db and tdulcet/ip-geolocation-dbs (hosted on GitLab). Independent-provider agreement is not a probability of correctness.