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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
26,289 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.195.222.0/24 | 256 | ARIN |  US | 6th Aug 1992 |
| 192.195.223.0/24 | 256 | ARIN | US | 6th Aug 1992 |
| 192.195.224.0/24 | 256 | ARIN | US | 27th Nov 1992 |
| 192.195.23.0/24 | 256 | ARIN | US | 10th Jul 1992 |
| 192.195.231.0/24 | 256 | ARIN | US | 6th Aug 1992 |
| 192.195.232.0/24 | 256 | ARIN | US | 6th Aug 1992 |
| 192.195.235.0/24 | 256 | ARIN | US | 7th Aug 1992 |
| 192.195.238.0/24 | 256 | ARIN | US | 7th Aug 1992 |
| 192.195.239.0/24 | 256 | ARIN | US | 7th Aug 1992 |
| 192.195.243.0/24 | 256 | ARIN | US | 7th Aug 1992 |
| 192.195.244.0/24 | 256 | ARIN | US | 7th Aug 1992 |
| 192.195.245.0/24 | 256 | ARIN | US | 7th Aug 1992 |
| 192.195.246.0/24 | 256 | ARIN | US | 11th Aug 1992 |
| 192.195.247.0/24 | 256 | ARIN | US | 11th Aug 1992 |
| 192.195.252.0/24 | 256 | ARIN | US | 11th Aug 1992 |
| 192.195.254.0/24 | 256 | ARIN | US | 12th Aug 1992 |
| 192.195.28.0/24 | 256 | ARIN | US | 10th Jul 1992 |
| 192.195.33.0/24 | 256 | ARIN | US | 14th Jul 1992 |
| 192.195.35.0/24 | 256 | ARIN | US | 14th Jul 1992 |
| 192.195.37.0/24 | 256 | ARIN | US | 15th Jul 1992 |
| 192.195.38.0/24 | 256 | ARIN | US | 15th Jul 1992 |
| 192.195.41.0/24 | 256 | ARIN | US | 15th Jul 1992 |
| 192.195.58.0/24 | 256 | ARIN | US | 17th Jul 1992 |
| 192.195.59.0/24 | 256 | ARIN | US | 17th Jul 1992 |
| 192.195.60.0/24 | 256 | ARIN | US | 17th Jul 1992 |
| 192.195.61.0/24 | 256 | ARIN | US | 17th Jul 1992 |
| 192.195.62.0/24 | 256 | ARIN | US | 17th Jul 1992 |
| 192.195.63.0/24 | 256 | ARIN | US | 17th Jul 1992 |
| 192.195.64.0/24 | 256 | ARIN | US | 17th Jul 1992 |
| 192.195.69.0/24 | 256 | ARIN | US | 17th Jul 1992 |
| 192.195.73.0/24 | 256 | ARIN | US | 17th Jul 1992 |
| 192.195.75.0/24 | 256 | ARIN | US | 21st Jul 1992 |
| 192.195.85.0/24 | 256 | ARIN | US | 21st Jul 1992 |
| 192.195.86.0/24 | 256 | ARIN | US | 21st Jul 1992 |
| 192.195.87.0/24 | 256 | ARIN | US | 21st Jul 1992 |
| 192.195.9.0/24 | 256 | ARIN | US | 9th Jul 1992 |
| 192.195.96.0/24 | 256 | ARIN | US | 21st Jul 1992 |
| 192.195.97.0/24 | 256 | ARIN | US | 21st Jul 1992 |
| 192.195.99.0/24 | 256 | ARIN | US | 21st Jul 1992 |
| 192.196.216.0/23 | 512 | ARIN | US | 21st Jun 2017 |
| 192.196.219.0/24 | 256 | ARIN | US | 18th May 2023 |
| 192.197.144.0/24 | 256 | ARIN | US | 2nd Nov 2018 |
| 192.197.158.0/24 | 256 | ARIN | US | 14th Jan 1993 |
| 192.197.159.0/24 | 256 | ARIN | US | 14th Jan 1993 |
| 192.197.160.0/24 | 256 | ARIN | US | 14th Jan 1993 |
| 192.197.199.0/24 | 256 | ARIN | US | 30th Mar 1993 |
| 192.197.200.0/24 | 256 | ARIN | US | 30th Mar 1993 |
| 192.197.224.0/24 | 256 | ARIN | US | 26th Feb 1993 |
| 192.198.16.0/21 | 2k | ARIN | US | 7th Apr 1997 |
| 192.198.187.0/24 | 256 | ARIN | US | 7th Mar 2013 |