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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,124 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.147.96.0/24 | 256 | ARIN |  US | 14th Feb 1992 |
| 192.147.97.0/24 | 256 | ARIN | US | 14th Feb 1992 |
| 192.147.98.0/24 | 256 | ARIN | US | 14th Feb 1992 |
| 192.147.99.0/24 | 256 | ARIN | US | 14th Feb 1992 |
| 192.148.100.0/24 | 256 | ARIN | US | 25th Feb 1992 |
| 192.148.101.0/24 | 256 | ARIN | US | 25th Feb 1992 |
| 192.148.102.0/24 | 256 | ARIN | US | 25th Feb 1992 |
| 192.148.103.0/24 | 256 | RIPE NCC |  PT | 5th Mar 1992 |
| 192.148.105.0/24 | 256 | ARIN | US | 26th Feb 1992 |
| 192.148.107.0/24 | 256 | ARIN | US | 26th Feb 1992 |
| 192.148.108.0/24 | 256 | ARIN | US | 26th Feb 1992 |
| 192.148.109.0/24 | 256 | ARIN | US | 26th Feb 1992 |
| 192.148.110.0/24 | 256 | ARIN | US | 26th Feb 1992 |
| 192.148.111.0/24 | 256 | ARIN |  CA | 19th May 2015 |
| 192.148.166.0/24 | 256 | RIPE NCC |  RU | 27th Feb 1992 |
| 192.148.168.0/24 | 256 | ARIN | US | 27th Feb 1992 |
| 192.148.169.0/24 | 256 | ARIN | US | 27th Feb 1992 |
| 192.148.170.0/24 | 256 | ARIN | US | 27th Feb 1992 |
| 192.148.171.0/24 | 256 | ARIN | US | 27th Feb 1992 |
| 192.148.172.0/24 | 256 | ARIN | US | 19th Apr 1993 |
| 192.148.174.0/24 | 256 | ARIN | US | 27th Feb 1992 |
| 192.148.175.0/24 | 256 | LACNIC |  MX | 27th Feb 1992 |
| 192.148.176.0/24 | 256 | ARIN | US | 27th Feb 1992 |
| 192.148.177.0/24 | 256 | RIPE NCC |  GB | 28th Feb 1992 |
| 192.148.178.0/24 | 256 | RIPE NCC | GB | 28th Feb 1992 |
| 192.148.179.0/24 | 256 | RIPE NCC | GB | 28th Feb 1992 |
| 192.148.180.0/24 | 256 | RIPE NCC | GB | 28th Feb 1992 |
| 192.148.181.0/24 | 256 | RIPE NCC | GB | 28th Feb 1992 |
| 192.148.182.0/24 | 256 | RIPE NCC | GB | 28th Feb 1992 |
| 192.148.183.0/24 | 256 | RIPE NCC | GB | 28th Feb 1992 |
| 192.148.184.0/24 | 256 | RIPE NCC | GB | 28th Feb 1992 |
| 192.148.185.0/24 | 256 | RIPE NCC | GB | 28th Feb 1992 |
| 192.148.186.0/24 | 256 | RIPE NCC | GB | 28th Feb 1992 |
| 192.148.187.0/24 | 256 | ARIN | US | 28th Feb 1992 |
| 192.148.188.0/24 | 256 | ARIN | US | 11th Jun 1996 |
| 192.148.189.0/24 | 256 | ARIN | US | 28th Feb 1992 |
| 192.148.191.0/24 | 256 | ARIN | US | 2nd Mar 1992 |
| 192.148.192.0/24 | 256 | RIPE NCC |  NL | 2nd Mar 1992 |
| 192.148.194.0/24 | 256 | RIPE NCC | GB | 2nd Mar 1992 |
| 192.148.198.0/24 | 256 | RIPE NCC | GB | 3rd Mar 1992 |
| 192.148.199.0/24 | 256 | RIPE NCC | GB | 3rd Mar 1992 |
| 192.148.200.0/24 | 256 | RIPE NCC | NL | 3rd Mar 1992 |
| 192.148.216.0/24 | 256 | RIPE NCC | GB | 3rd Mar 1992 |
| 192.148.219.0/24 | 256 | ARIN | US | 14th May 2015 |
| 192.148.220.0/24 | 256 | RIPE NCC |  IT | 4th Mar 1992 |
| 192.148.222.0/24 | 256 | ARIN | US | 4th Mar 1992 |
| 192.148.230.0/24 | 256 | APNIC |  AU | 4th Mar 1992 |
| 192.148.231.0/24 | 256 | ARIN | US | 4th Mar 1992 |
| 192.148.232.0/24 | 256 | ARIN | US | 4th Mar 1992 |
| 192.148.233.0/24 | 256 | ARIN | US | 4th Mar 1992 |