RFC 8805 validator
Check a geofeed before providers do.
The format
One prefix per line, five comma-separated fields:
prefix,country_code,region_code,city,postal
- prefix
- IPv4 or IPv6 prefix in CIDR notation
- country_code
- ISO 3166-1 alpha-2 country code
- region_code
- ISO 3166-2 subdivision code
- city
- City name
- postal
- Postal code
Lines starting with # are comments. Every field except the prefix may be empty.