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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 unannounced space registered through ARIN, largest first.
Unannounced blocks in United States
26,302 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 198.178.215.0/24 | 256 | ARIN |  US | 26th Jul 1993 |
| 198.178.217.0/24 | 256 | ARIN | US | 26th Jul 1993 |
| 198.178.221.0/24 | 256 | ARIN | US | 27th Jul 1993 |
| 198.178.222.0/24 | 256 | ARIN | US | 27th Jul 1993 |
| 198.178.227.0/24 | 256 | ARIN | US | 27th Jul 1993 |
| 198.178.228.0/24 | 256 | ARIN | US | 27th Jul 1993 |
| 198.178.229.0/24 | 256 | ARIN | US | 28th Jul 1993 |
| 198.178.230.0/24 | 256 | ARIN | US | 28th Jul 1993 |
| 198.178.233.0/24 | 256 | ARIN | US | 29th Jul 1993 |
| 198.178.24.0/22 | 1k | ARIN | US | 28th May 1993 |
| 198.178.240.0/23 | 512 | ARIN | US | 30th Jul 1993 |
| 198.178.242.0/24 | 256 | ARIN | US | 30th Jul 1993 |
| 198.178.243.0/24 | 256 | ARIN | US | 30th Jul 1993 |
| 198.178.246.0/24 | 256 | ARIN | US | 30th Jul 1993 |
| 198.178.247.0/24 | 256 | ARIN | US | 30th Jul 1993 |
| 198.178.248.0/24 | 256 | ARIN | US | 30th Jul 1993 |
| 198.178.252.0/23 | 512 | ARIN | US | 30th Jul 1993 |
| 198.179.128.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.179.129.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.179.131.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.179.132.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.179.133.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.179.134.0/24 | 256 | ARIN | US | 5th Mar 2013 |
| 198.179.135.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.179.136.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.179.137.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.179.138.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.179.139.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.179.140.0/24 | 256 | ARIN | US | 26th May 1994 |
| 198.179.141.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 198.179.142.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 198.179.143.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 198.179.144.0/23 | 512 | ARIN | US | 21st Oct 1993 |
| 198.179.146.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 198.179.147.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 198.179.148.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 198.179.149.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 198.179.150.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 198.179.16.0/24 | 256 | ARIN | US | 28th Jun 1993 |
| 198.179.160.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 198.179.161.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 198.179.169.0/24 | 256 | ARIN | US | 25th Oct 1993 |
| 198.179.17.0/24 | 256 | ARIN | US | 28th Jun 1993 |
| 198.179.174.0/24 | 256 | ARIN | US | 25th Oct 1993 |
| 198.179.175.0/24 | 256 | ARIN | US | 25th Oct 1993 |
| 198.179.176.0/24 | 256 | ARIN | US | 25th Oct 1993 |
| 198.179.178.0/24 | 256 | ARIN | US | 26th Oct 1993 |
| 198.179.179.0/24 | 256 | ARIN | US | 26th Oct 1993 |
| 198.179.180.0/24 | 256 | ARIN | US | 26th Oct 1993 |
| 198.179.186.0/24 | 256 | ARIN | US | 27th Oct 1993 |