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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 unannounced space registered through ARIN, largest first.
Unannounced blocks in United States
26,315 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 199.103.114.0/23 | 512 | ARIN |  US | 26th Jun 1994 |
| 199.103.116.0/23 | 512 | ARIN | US | 26th Jun 1994 |
| 199.103.120.0/23 | 512 | ARIN | US | 26th Jun 1994 |
| 199.103.13.0/24 | 256 | ARIN | US | 11th Jan 1994 |
| 199.103.14.0/23 | 512 | ARIN | US | 11th Jan 1994 |
| 199.103.22.0/23 | 512 | ARIN | US | 23rd Aug 2019 |
| 199.103.69.0/24 | 256 | ARIN | US | 25th Jun 1994 |
| 199.103.70.0/23 | 512 | ARIN | US | 25th Jun 1994 |
| 199.103.72.0/24 | 256 | ARIN | US | 25th Jun 1994 |
| 199.103.78.0/23 | 512 | ARIN | US | 25th Jun 1994 |
| 199.103.80.0/24 | 256 | ARIN | US | 25th Jun 1994 |
| 199.103.84.0/24 | 256 | ARIN | US | 25th Jun 1994 |
| 199.103.87.0/24 | 256 | ARIN | US | 1st Jul 2026 |
| 199.103.89.0/24 | 256 | ARIN | US | 19th Jul 2019 |
| 199.103.94.0/23 | 512 | ARIN | US | 25th Jun 1994 |
| 199.104.10.0/24 | 256 | ARIN | US | 24th Jul 2025 |
| 199.104.106.0/23 | 512 | ARIN | US | 10th Jan 1994 |
| 199.104.108.0/22 | 1k | ARIN | US | 10th Jan 1994 |
| 199.104.12.0/23 | 512 | ARIN | US | 10th Jan 1994 |
| 199.104.16.0/22 | 1k | ARIN | US | 10th Jan 1994 |
| 199.104.20.0/24 | 256 | ARIN | US | 6th Feb 2026 |
| 199.104.32.0/19 | 8.2k | ARIN | US | 10th Jan 1994 |
| 199.104.68.0/23 | 512 | ARIN | US | 10th Jan 1994 |
| 199.104.71.0/24 | 256 | ARIN | US | 10th Jan 1994 |
| 199.104.72.0/22 | 1k | ARIN | US | 10th Jan 1994 |
| 199.104.78.0/23 | 512 | ARIN | US | 10th Jan 1994 |
| 199.104.8.0/24 | 256 | ARIN | US | 24th Jul 2025 |
| 199.104.88.0/23 | 512 | ARIN | US | 10th Jan 1994 |
| 199.104.90.0/24 | 256 | ARIN | US | 10th Jan 1994 |
| 199.104.94.0/24 | 256 | ARIN | US | 10th Jan 1994 |
| 199.104.96.0/21 | 2k | ARIN | US | 10th Jan 1994 |
| 199.114.0.0/23 | 512 | ARIN | US | 14th Mar 1994 |
| 199.114.12.0/24 | 256 | ARIN | US | 22nd Feb 1994 |
| 199.114.13.0/24 | 256 | ARIN | US | 26th Feb 2021 |
| 199.114.2.0/23 | 512 | ARIN | US | 25th Jan 1994 |
| 199.114.212.0/22 | 1k | ARIN | US | 23rd Feb 2012 |
| 199.114.224.0/22 | 1k | ARIN | US | 24th Feb 2012 |
| 199.114.4.0/23 | 512 | ARIN | US | 25th Jan 1994 |
| 199.114.6.0/24 | 256 | ARIN | US | 25th Jan 1994 |
| 199.114.8.0/22 | 1k | ARIN | US | 22nd Feb 1994 |
| 199.115.106.0/23 | 512 | ARIN | US | 2nd Mar 2012 |
| 199.115.108.0/24 | 256 | ARIN | US | 2nd Mar 2012 |
| 199.115.109.0/24 | 256 | ARIN | US | 2nd Mar 2012 |
| 199.115.159.0/24 | 256 | ARIN | US | 19th Sept 2012 |
| 199.115.160.0/22 | 1k | ARIN | US | 20th Apr 2011 |
| 199.115.174.0/24 | 256 | ARIN | US | 6th May 2026 |
| 199.115.31.0/24 | 256 | ARIN | US | 7th Apr 2016 |
| 199.115.48.0/22 | 1k | ARIN | US | 22nd Feb 1994 |
| 199.115.52.0/23 | 512 | ARIN | US | 22nd Feb 1994 |
| 199.115.84.0/22 | 1k | ARIN | US | 1st Mar 2012 |