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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 198.181.244.0/24 | 256 | ARIN |  US | 6th Dec 1993 |
| 198.181.245.0/24 | 256 | ARIN | US | 6th Dec 1993 |
| 198.181.246.0/23 | 512 | ARIN | US | 6th Dec 1993 |
| 198.181.251.0/24 | 256 | ARIN | US | 7th Dec 1993 |
| 198.181.64.0/19 | 8.2k | ARIN | US | 2nd Dec 1993 |
| 198.181.96.0/20 | 4.1k | ARIN | US | 2nd Dec 1993 |
| 198.182.128.0/23 | 512 | ARIN | US | 17th Aug 1993 |
| 198.182.132.0/23 | 512 | ARIN | US | 18th Aug 1993 |
| 198.182.134.0/24 | 256 | ARIN | US | 18th Aug 1993 |
| 198.182.135.0/24 | 256 | ARIN | US | 18th Aug 1993 |
| 198.182.136.0/24 | 256 | ARIN | US | 18th Aug 1993 |
| 198.182.137.0/24 | 256 | ARIN | US | 18th Aug 1993 |
| 198.182.138.0/24 | 256 | ARIN | US | 18th Aug 1993 |
| 198.182.139.0/24 | 256 | ARIN | US | 18th Aug 1993 |
| 198.182.141.0/24 | 256 | ARIN | US | 19th Aug 1993 |
| 198.182.142.0/24 | 256 | ARIN | US | 19th Aug 1993 |
| 198.182.143.0/24 | 256 | ARIN | US | 19th Aug 1993 |
| 198.182.144.0/22 | 1k | ARIN | US | 19th Aug 1993 |
| 198.182.148.0/24 | 256 | ARIN | US | 19th Aug 1993 |
| 198.182.149.0/24 | 256 | ARIN | US | 19th Aug 1993 |
| 198.182.150.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.151.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.156.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.158.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.160.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.164.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.165.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.166.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.168.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.169.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.170.0/24 | 256 | ARIN |  BM | 23rd Aug 1993 |
| 198.182.172.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.173.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.175.0/24 | 256 | ARIN | US | 23rd Aug 1993 |
| 198.182.183.0/24 | 256 | ARIN | US | 25th Aug 1993 |
| 198.182.184.0/24 | 256 | ARIN | US | 25th Aug 1993 |
| 198.182.185.0/24 | 256 | ARIN | US | 25th Aug 1993 |
| 198.182.186.0/23 | 512 | ARIN | US | 25th Aug 1993 |
| 198.182.188.0/23 | 512 | ARIN | US | 25th Aug 1993 |
| 198.182.190.0/24 | 256 | ARIN | US | 25th Aug 1993 |
| 198.182.195.0/24 | 256 | ARIN | US | 25th Aug 1993 |
| 198.182.196.0/24 | 256 | ARIN | US | 25th Aug 1993 |
| 198.182.197.0/24 | 256 | ARIN | US | 25th Aug 1993 |
| 198.182.200.0/23 | 512 | ARIN | US | 26th Aug 1993 |
| 198.182.202.0/24 | 256 | ARIN | US | 27th Aug 1993 |
| 198.182.203.0/24 | 256 | ARIN | US | 27th Aug 1993 |
| 198.182.204.0/24 | 256 | ARIN | US | 27th Aug 1993 |
| 198.182.206.0/24 | 256 | ARIN | US | 27th Aug 1993 |
| 198.182.209.0/24 | 256 | ARIN | US | 27th Aug 1993 |
| 198.182.210.0/23 | 512 | ARIN | US | 27th Aug 1993 |