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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
27,014 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.223.8.0/24 | 256 | ARIN |  US | 11th Sept 1992 |
| 192.224.0.0/16 | 65.5k | ARIN | US | 15th Sept 1992 |
| 192.225.100.0/22 | 1k | ARIN | US | 30th Aug 2019 |
| 192.225.108.0/24 | 256 | ARIN | US | 22nd Nov 2019 |
| 192.225.109.0/24 | 256 | ARIN | US | 6th Apr 2026 |
| 192.225.24.0/23 | 512 | ARIN | US | 15th Sept 1992 |
| 192.225.28.0/22 | 1k | ARIN | US | 11th Feb 2013 |
| 192.225.32.0/20 | 4.1k | ARIN | US | 16th Sept 1992 |
| 192.225.48.0/21 | 2k | ARIN | US | 16th Sept 1992 |
| 192.225.56.0/24 | 256 | ARIN | US | 16th Sept 1992 |
| 192.225.59.0/24 | 256 | ARIN | US | 30th Apr 2015 |
| 192.225.97.0/24 | 256 | ARIN | US | 9th Sept 2019 |
| 192.226.0.0/21 | 2k | ARIN | US | 15th Mar 2013 |
| 192.226.16.0/20 | 4.1k | ARIN | US | 17th Sept 1992 |
| 192.226.8.0/21 | 2k | ARIN | US | 17th Sept 1992 |
| 192.228.72.0/22 | 1k | ARIN | US | 8th Oct 1992 |
| 192.228.76.0/23 | 512 | ARIN | US | 8th Oct 1992 |
| 192.228.78.0/24 | 256 | ARIN | US | 8th Oct 1992 |
| 192.228.88.0/22 | 1k | ARIN | US | 14th Jul 2003 |
| 192.228.93.0/24 | 256 | ARIN | US | 4th Jan 2016 |
| 192.229.128.0/17 | 32.8k | ARIN | US | 7th Feb 2013 |
| 192.229.32.0/19 | 8.2k | ARIN | US | 28th Sept 1992 |
| 192.230.224.0/22 | 1k | ARIN | US | 9th May 2013 |
| 192.230.228.0/23 | 512 | ARIN | US | 9th May 2013 |
| 192.230.231.0/24 | 256 | ARIN | US | 9th May 2013 |
| 192.230.232.0/21 | 2k | ARIN | US | 9th May 2013 |
| 192.230.32.0/19 | 8.2k | ARIN | US | 22nd Feb 2013 |
| 192.231.0.0/24 | 256 | ARIN | US | 28th Jul 2015 |
| 192.231.1.0/24 | 256 | ARIN | US | 21st Sept 1992 |
| 192.231.100.0/24 | 256 | ARIN | US | 2nd Oct 1992 |
| 192.231.101.0/24 | 256 | ARIN | US | 2nd Oct 1992 |
| 192.231.102.0/24 | 256 | ARIN | US | 2nd Oct 1992 |
| 192.231.103.0/24 | 256 | ARIN | US | 2nd Oct 1992 |
| 192.231.104.0/24 | 256 | ARIN | US | 2nd Oct 1992 |
| 192.231.105.0/24 | 256 | ARIN | US | 2nd Oct 1992 |
| 192.231.107.0/24 | 256 | ARIN | US | 2nd Oct 1992 |
| 192.231.108.0/24 | 256 | ARIN | US | 2nd Oct 1992 |
| 192.231.11.0/24 | 256 | ARIN | US | 22nd Sept 1992 |
| 192.231.111.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.231.12.0/24 | 256 | ARIN | US | 22nd Sept 1992 |
| 192.231.126.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.231.129.0/24 | 256 | ARIN | US | 7th Oct 1992 |
| 192.231.13.0/24 | 256 | ARIN | US | 22nd Sept 1992 |
| 192.231.138.0/24 | 256 | ARIN | US | 8th Oct 1992 |
| 192.231.139.0/24 | 256 | ARIN | US | 8th Oct 1992 |
| 192.231.14.0/24 | 256 | ARIN | US | 22nd Sept 1992 |
| 192.231.142.0/24 | 256 | ARIN | US | 8th Oct 1992 |
| 192.231.148.0/24 | 256 | ARIN | US | 9th Oct 1992 |
| 192.231.149.0/24 | 256 | ARIN | US | 24th Jul 1996 |
| 192.231.150.0/24 | 256 | ARIN | US | 9th Oct 1992 |