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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 unannounced space registered through ARIN, largest first.
Unannounced blocks in United States
26,302 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 204.62.222.0/24 | 256 | ARIN |  US | 10th Aug 1994 |
| 204.62.223.0/24 | 256 | ARIN | US | 10th Aug 1994 |
| 204.62.224.0/22 | 1k | ARIN | US | 10th Aug 1994 |
| 204.62.228.0/23 | 512 | ARIN | US | 10th Aug 1994 |
| 204.62.230.0/24 | 256 | ARIN | US | 10th Aug 1994 |
| 204.62.232.0/24 | 256 | ARIN | US | 11th Aug 1994 |
| 204.62.236.0/22 | 1k | ARIN | US | 12th Aug 1994 |
| 204.62.240.0/23 | 512 | ARIN | US | 12th Aug 1994 |
| 204.62.242.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.62.243.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.62.244.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.62.245.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.62.250.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.62.251.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.62.252.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.62.253.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.62.254.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.62.255.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.63.128.0/22 | 1k | ARIN | US | 31st Oct 1994 |
| 204.63.132.0/24 | 256 | ARIN | US | 31st Oct 1994 |
| 204.63.134.0/23 | 512 | ARIN | US | 3rd Jun 2011 |
| 204.63.172.0/24 | 256 | ARIN | US | 12th Sept 2018 |
| 204.63.184.0/22 | 1k | ARIN | US | 21st Nov 1994 |
| 204.63.188.0/23 | 512 | ARIN | US | 21st Nov 1994 |
| 204.63.212.0/24 | 256 | ARIN | US | 28th Nov 1994 |
| 204.63.213.0/24 | 256 | ARIN | US | 22nd Aug 2011 |
| 204.63.64.0/18 | 16.4k | ARIN | US | 10th Oct 1994 |
| 204.68.0.0/21 | 2k | ARIN | US | 26th Apr 1994 |
| 204.68.132.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.68.133.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.68.134.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 204.68.135.0/24 | 256 | ARIN | US | 17th Aug 1994 |
| 204.68.136.0/21 | 2k | ARIN | US | 17th Aug 1994 |
| 204.68.144.0/22 | 1k | ARIN | US | 17th Aug 1994 |
| 204.68.148.0/24 | 256 | ARIN | US | 17th Aug 1994 |
| 204.68.149.0/24 | 256 | ARIN | US | 17th Aug 1994 |
| 204.68.150.0/24 | 256 | ARIN | US | 17th Aug 1994 |
| 204.68.151.0/24 | 256 | ARIN | US | 17th Aug 1994 |
| 204.68.155.0/24 | 256 | ARIN | US | 18th Aug 1994 |
| 204.68.156.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.157.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.158.0/23 | 512 | ARIN | US | 19th Aug 1994 |
| 204.68.160.0/22 | 1k | ARIN | US | 19th Aug 1994 |
| 204.68.164.0/23 | 512 | ARIN | US | 19th Aug 1994 |
| 204.68.166.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.167.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.168.0/24 | 256 | ARIN | US | 1st Mar 2017 |
| 204.68.169.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.172.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.173.0/24 | 256 | ARIN | US | 19th Aug 1994 |