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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,285 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 199.185.144.0/20 | 4.1k | ARIN |  CA | 22nd Feb 1994 |
| 199.185.16.0/21 | 2k | ARIN | CA | 22nd Feb 1994 |
| 199.185.160.0/21 | 2k | ARIN | CA | 22nd Feb 1994 |
| 199.185.169.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.170.0/23 | 512 | ARIN | CA | 22nd Feb 1994 |
| 199.185.172.0/23 | 512 | ARIN | CA | 22nd Feb 1994 |
| 199.185.179.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.183.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.186.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.187.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.212.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.213.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.214.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.216.0/22 | 1k | ARIN | CA | 22nd Feb 1994 |
| 199.185.220.0/22 | 1k | ARIN | CA | 22nd Feb 1994 |
| 199.185.224.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.232.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.234.0/23 | 512 | ARIN | CA | 22nd Feb 1994 |
| 199.185.236.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.237.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.238.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.239.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.24.0/22 | 1k | ARIN | CA | 22nd Feb 1994 |
| 199.185.245.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.246.0/23 | 512 | ARIN | CA | 22nd Feb 1994 |
| 199.185.250.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.251.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.254.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.255.0/24 | 256 | ARIN | CA | 22nd May 1995 |
| 199.185.28.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.4.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.8.0/23 | 512 | ARIN | CA | 22nd Feb 1994 |
| 199.185.96.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.97.0/24 | 256 | ARIN |  US | 9th Jul 2012 |
| 199.185.98.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.185.99.0/24 | 256 | ARIN | CA | 22nd Feb 1994 |
| 199.187.0.0/21 | 2k | ARIN | US | 3rd Mar 1994 |
| 199.187.112.0/23 | 512 | ARIN | US | 24th Feb 1994 |
| 199.187.152.0/21 | 2k | ARIN | US | 19th Jul 2011 |
| 199.187.164.0/22 | 1k | ARIN | US | 20th Jul 2011 |
| 199.187.192.0/22 | 1k | ARIN | CA | 22nd Jul 2011 |
| 199.187.216.0/21 | 2k | ARIN | US | 14th Jul 2022 |
| 199.187.32.0/20 | 4.1k | ARIN | US | 24th Feb 1994 |
| 199.187.48.0/21 | 2k | ARIN | US | 24th Feb 1994 |
| 199.187.56.0/24 | 256 | ARIN | US | 24th Feb 1994 |
| 199.187.57.0/24 | 256 | ARIN | US | 4th Oct 1994 |
| 199.187.58.0/23 | 512 | ARIN | US | 4th Oct 1994 |
| 199.187.60.0/22 | 1k | ARIN | US | 4th Oct 1994 |
| 199.187.96.0/20 | 4.1k | ARIN | US | 24th Feb 1994 |
| 199.188.144.0/22 | 1k | ARIN | US | 8th Jul 2026 |