Accuracy and freshness methodology
Where Fastah’s IP data comes from, how often it changes, and what we do and don’t measure. We don’t publish accuracy percentages until we have measured them.
Where the data comes from
- Self-published geofeeds. RFC 8805 files in which networks state where their own addresses are, found through the networks’ registry records (RFC 9632). The geofeed catalog lists some of the feeds networks publish.
- Registration data from the regional internet registries, through WHOIS and RDAP.
- Public routing and AS-organization data, for which network an address belongs to.
- Place names from GeoNames (CC BY 4.0).
How often it changes
Fastah rebuilds its IP data every day. IP address and IP range pages on this site show the build their record came from as “Data as of”.
How quickly a network’s own correction reaches the data matters as much as the rebuild schedule. GeolocateMuch, an independent site that tracks geofeed adoption, measures it: it publishes new geofeeds in registry records and counts the days until each provider’s data reflects them.
This measures geofeed pickup. It is not a measure of overall accuracy.
How locations are expressed
A location is an area, not a point. Each record names the kind of place it describes (a city, a region or a country), and the API returns an accuracy radius. A city-level answer means “in or near this city”, not a street address. IP-derived locations are approximate and are not proof of identity or of an exact physical location.
What we don’t claim yet
- No accuracy percentages. We haven’t published a measured accuracy benchmark. When we do, this page will describe the method and the reference data.
- No coverage percentages. Likewise for the share of address space each kind of source covers.
Found an error?
Send a data correction for one address or prefix. If you run the network, a geofeed fixes it for every provider at once. More background: why is my IP location wrong?