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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,248 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 198.183.160.0/22 | 1k | ARIN |  US | 7th Sept 1993 |
| 198.183.170.0/24 | 256 | ARIN | US | 7th Sept 1993 |
| 198.183.171.0/24 | 256 | ARIN | US | 7th Sept 1993 |
| 198.183.173.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.174.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.175.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.176.0/23 | 512 | ARIN | US | 8th Sept 1993 |
| 198.183.188.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.189.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.190.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.191.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.192.0/23 | 512 | ARIN | US | 8th Sept 1993 |
| 198.183.194.0/24 | 256 | ARIN | US | 5th Aug 2026 |
| 198.183.195.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.196.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.198.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.199.0/24 | 256 | ARIN | US | 8th Sept 1993 |
| 198.183.2.0/24 | 256 | ARIN | US | 1st Jun 1993 |
| 198.183.204.0/24 | 256 | ARIN | US | 9th Sept 1993 |
| 198.183.205.0/24 | 256 | ARIN | US | 9th Sept 1993 |
| 198.183.210.0/23 | 512 | ARIN | US | 9th Sept 1993 |
| 198.183.212.0/22 | 1k | ARIN | US | 9th Sept 1993 |
| 198.183.216.0/24 | 256 | ARIN | US | 9th Sept 1993 |
| 198.183.217.0/24 | 256 | ARIN | US | 9th Sept 1993 |
| 198.183.218.0/24 | 256 | ARIN | US | 9th Sept 1993 |
| 198.183.219.0/24 | 256 | ARIN | US | 19th Feb 2013 |
| 198.183.224.0/24 | 256 | ARIN | US | 9th Sept 1993 |
| 198.183.225.0/24 | 256 | ARIN |  CA | 21st Feb 2013 |
| 198.183.228.0/22 | 1k | ARIN | US | 9th Sept 1993 |
| 198.183.232.0/22 | 1k | ARIN | US | 9th Sept 1993 |
| 198.183.236.0/23 | 512 | ARIN | US | 9th Sept 1993 |
| 198.183.238.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.183.239.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.183.240.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.183.246.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.183.247.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.183.250.0/24 | 256 | ARIN | US | 13th Sept 1993 |
| 198.183.254.0/24 | 256 | ARIN | US | 13th Sept 1993 |
| 198.183.32.0/19 | 8.2k | ARIN | US | 10th Sept 1993 |
| 198.183.64.0/18 | 16.4k | ARIN | US | 5th Aug 1993 |
| 198.184.12.0/24 | 256 | ARIN | US | 9th Feb 1994 |
| 198.184.128.0/24 | 256 | ARIN | US | 7th Dec 1993 |
| 198.184.129.0/24 | 256 | ARIN | US | 7th Dec 1993 |
| 198.184.130.0/24 | 256 | ARIN | US | 7th Dec 1993 |
| 198.184.132.0/24 | 256 | ARIN | US | 7th Dec 1993 |
| 198.184.133.0/24 | 256 | ARIN | US | 7th Dec 1993 |
| 198.184.134.0/24 | 256 | ARIN | US | 7th Dec 1993 |
| 198.184.136.0/24 | 256 | ARIN | US | 7th Dec 1993 |
| 198.184.137.0/24 | 256 | ARIN | US | 9th Dec 1993 |
| 198.184.138.0/24 | 256 | ARIN | US | 9th Dec 1993 |