- Where do the addresses come from?
- The blocks come from the daily delegation statistics of the five regional internet registries (ARIN, RIPE NCC, APNIC, LACNIC and AFRINIC): every IPv4 range and IPv6 prefix assigned to a holder registered in the United Kingdom. An address is picked at random across all of them, so bigger networks come up more often.
- Will a geo-IP lookup place them in the United Kingdom?
- Usually. The registry records the country of the network's holder, and most geo-IP databases agree, but some blocks are used abroad (cloud providers, VPNs, multinational carriers), so a lookup can disagree for a few addresses.
- Can I scan or connect to these addresses?
- No. They belong to real networks and may be in use. Use them as test data for logs, firewall rules, geo-IP logic and form validation, never to probe or attack anyone.
- What are the private and documentation ranges?
- Private addresses (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 and IPv6 fd00::/8) are for internal networks and never routed on the internet. Documentation addresses (192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24 and 2001:db8::/32) are reserved for examples, so they are the safest choice for docs and screenshots.