Allocated but unannounced space
Every block here was allocated or assigned by a regional internet registry, and none of them appeared in any routing table we collected at our last snapshot — neither as a route of their own, nor covered by a larger announcement, nor carved up into more specifics.
“Unannounced” does not mean “unused”
Plenty of allocated space is deliberately kept off the public internet: private interconnects, lab and lawful-intercept ranges, networks reachable only inside one operator, and space held in reserve. Some of it is announced somewhere our collectors cannot see, which is a limit of our vantage points rather than a fact about the block.
It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today. Nothing on this page means a block is unallocated, available, or free to announce.
Browse by registry
Browse by country
Countries with the most unannounced blocks, largest first.
Unannounced blocks
85,201 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.247.4.0/22 | 1k | RIPE NCC |  GB | 26th Oct 1992 |
| 192.247.8.0/23 | 512 | RIPE NCC | GB | 26th Oct 1992 |
| 192.247.96.0/19 | 8.2k | ARIN |  US | 19th Mar 2013 |
| 192.25.0.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.10.0/24 | 256 | ARIN | US | 13th Feb 2020 |
| 192.25.100.0/24 | 256 | ARIN | US | 2nd Mar 2000 |
| 192.25.101.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.104.0/23 | 512 | ARIN | US | 8th Aug 1986 |
| 192.25.106.0/24 | 256 | ARIN | US | 24th Feb 2001 |
| 192.25.107.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.108.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.112.0/23 | 512 | ARIN | US | 8th Aug 1986 |
| 192.25.114.0/24 | 256 | ARIN | US | 24th Feb 2001 |
| 192.25.118.0/23 | 512 | ARIN | US | 8th Aug 1986 |
| 192.25.120.0/23 | 512 | ARIN | US | 8th Aug 1986 |
| 192.25.122.0/23 | 512 | ARIN | US | 24th Feb 2001 |
| 192.25.127.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.128.0/22 | 1k | ARIN | US | 8th Aug 1986 |
| 192.25.132.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.133.0/24 | 256 | ARIN | US | 20th Dec 2000 |
| 192.25.134.0/24 | 256 | ARIN | US | 2nd Mar 2000 |
| 192.25.135.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.136.0/23 | 512 | ARIN | US | 8th Aug 1986 |
| 192.25.140.0/23 | 512 | ARIN | US | 24th Feb 2001 |
| 192.25.143.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.144.0/23 | 512 | ARIN | US | 24th Feb 2001 |
| 192.25.146.0/23 | 512 | ARIN | US | 8th Aug 1986 |
| 192.25.15.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.150.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.153.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.154.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.155.0/24 | 256 | ARIN | US | 2nd Mar 2000 |
| 192.25.156.0/23 | 512 | ARIN | US | 8th Aug 1986 |
| 192.25.158.0/23 | 512 | ARIN | US | 8th Aug 1986 |
| 192.25.16.0/23 | 512 | ARIN | US | 8th Aug 1986 |
| 192.25.168.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.170.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.171.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.172.0/22 | 1k | ARIN | US | 8th Aug 1986 |
| 192.25.176.0/22 | 1k | ARIN | US | 8th Aug 1986 |
| 192.25.18.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.184.0/23 | 512 | ARIN | US | 8th Aug 1986 |
| 192.25.186.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.187.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.188.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.189.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.190.0/24 | 256 | ARIN | US | 8th Aug 1986 |
| 192.25.191.0/24 | 256 | ARIN | US | 2nd Mar 2000 |
| 192.25.192.0/22 | 1k | ARIN | US | 8th Aug 1986 |
| 192.25.196.0/24 | 256 | ARIN | US | 8th Aug 1986 |