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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
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Countries with the most unannounced blocks, largest first.
Unannounced blocks in United States
27,021 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 204.62.214.0/24 | 256 | ARIN |  US | 10th Aug 1994 |
| 204.62.216.0/23 | 512 | ARIN | US | 2nd Jun 2021 |
| 204.62.219.0/24 | 256 | ARIN | US | 10th Aug 1994 |
| 204.62.220.0/23 | 512 | ARIN | US | 10th Aug 1994 |
| 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 |