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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 in United States
26,955 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.189.181.0/24 | 256 | ARIN |  US | 28th Jul 1992 |
| 192.189.182.0/24 | 256 | ARIN | US | 28th Jul 1992 |
| 192.189.188.0/24 | 256 | ARIN | US | 28th Jul 1992 |
| 192.189.189.0/24 | 256 | ARIN | US | 28th Jul 1992 |
| 192.189.19.0/24 | 256 | ARIN | US | 17th Jun 1992 |
| 192.189.190.0/24 | 256 | ARIN | US | 28th Jul 1992 |
| 192.189.191.0/24 | 256 | ARIN | US | 28th Jul 1992 |
| 192.189.195.0/24 | 256 | ARIN | US | 22nd Jul 2020 |
| 192.189.20.0/24 | 256 | ARIN | US | 17th Jun 1992 |
| 192.189.200.0/23 | 512 | ARIN | US | 6th Apr 2015 |
| 192.189.206.0/24 | 256 | ARIN | US | 29th Jul 1992 |
| 192.189.212.0/24 | 256 | ARIN | US | 30th Jul 1992 |
| 192.189.213.0/24 | 256 | ARIN | US | 30th Jul 1992 |
| 192.189.214.0/24 | 256 | ARIN | US | 30th Jul 1992 |
| 192.189.221.0/24 | 256 | ARIN | US | 31st Jul 1992 |
| 192.189.222.0/24 | 256 | ARIN | US | 31st Jul 1992 |
| 192.189.224.0/24 | 256 | ARIN | US | 31st Jul 1992 |
| 192.189.225.0/24 | 256 | ARIN | US | 31st Jul 1992 |
| 192.189.228.0/24 | 256 | ARIN | US | 31st Jul 1992 |
| 192.189.236.0/24 | 256 | ARIN | US | 4th Aug 1992 |
| 192.189.239.0/24 | 256 | ARIN | US | 3rd Aug 1992 |
| 192.189.240.0/24 | 256 | ARIN | US | 3rd Aug 1992 |
| 192.189.241.0/24 | 256 | ARIN | US | 3rd Aug 1992 |
| 192.189.242.0/24 | 256 | ARIN | US | 3rd Aug 1992 |
| 192.189.243.0/24 | 256 | ARIN | US | 3rd Aug 1992 |
| 192.189.245.0/24 | 256 | ARIN | US | 3rd Aug 1992 |
| 192.189.246.0/24 | 256 | ARIN | US | 3rd Aug 1992 |
| 192.189.250.0/24 | 256 | ARIN | US | 3rd Aug 1992 |
| 192.189.254.0/24 | 256 | ARIN | US | 3rd Aug 1992 |
| 192.189.30.0/24 | 256 | ARIN | US | 18th Jun 1992 |
| 192.189.31.0/24 | 256 | ARIN | US | 18th Jun 1992 |
| 192.189.32.0/24 | 256 | ARIN | US | 18th Jun 1992 |
| 192.189.33.0/24 | 256 | ARIN | US | 18th Jun 1992 |
| 192.189.35.0/24 | 256 | ARIN | US | 18th Jun 1992 |
| 192.189.43.0/24 | 256 | ARIN | US | 30th Jun 1992 |
| 192.189.44.0/24 | 256 | ARIN | US | 30th Jun 1992 |
| 192.189.49.0/24 | 256 | ARIN | US | 2nd Jul 2026 |
| 192.189.50.0/24 | 256 | ARIN | US | 2nd Jul 2026 |
| 192.189.53.0/24 | 256 | ARIN | US | 1st Jul 1992 |
| 192.189.56.0/24 | 256 | ARIN | US | 1st Jul 1992 |
| 192.189.57.0/24 | 256 | ARIN | US | 1st Jul 1992 |
| 192.189.59.0/24 | 256 | ARIN | US | 30th Jul 2015 |
| 192.189.61.0/24 | 256 | ARIN | US | 9th Jul 1992 |
| 192.189.62.0/24 | 256 | ARIN | US | 9th Jul 1992 |
| 192.189.63.0/24 | 256 | ARIN | US | 9th Jul 1992 |
| 192.189.64.0/24 | 256 | ARIN | US | 9th Jul 1992 |
| 192.189.7.0/24 | 256 | ARIN | US | 17th Jun 1992 |
| 192.189.72.0/24 | 256 | ARIN | US | 23rd May 2016 |
| 192.189.74.0/24 | 256 | ARIN | US | 18th May 1995 |
| 192.189.77.0/24 | 256 | ARIN | US | 10th Jul 1992 |