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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,221 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.88.215.0/24 | 256 | ARIN |  US | 11th Jan 1991 |
| 192.88.216.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.217.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.22.0/24 | 256 | ARIN | US | 5th Dec 1990 |
| 192.88.220.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.221.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.222.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.223.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.224.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.225.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.226.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.227.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.228.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.229.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.230.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.231.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.232.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.233.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.234.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.235.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.237.0/24 | 256 | ARIN | US | 17th Jan 1991 |
| 192.88.238.0/24 | 256 | RIPE NCC |  GB | 17th Jan 1991 |
| 192.88.239.0/24 | 256 | RIPE NCC |  DE | 17th Jan 1991 |
| 192.88.241.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.243.0/24 | 256 | ARIN | US | 28th May 2025 |
| 192.88.244.0/24 | 256 | ARIN | US | 11th Jan 1991 |
| 192.88.245.0/24 | 256 | ARIN | US | 15th Jan 1991 |
| 192.88.246.0/23 | 512 | ARIN | US | 15th Jan 1991 |
| 192.88.28.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.29.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.3.0/24 | 256 | ARIN | US | 28th Nov 1990 |
| 192.88.5.0/24 | 256 | ARIN | US | 28th Nov 1990 |
| 192.88.51.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.52.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.53.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.55.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.56.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.57.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.58.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.59.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.63.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.64.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.65.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.66.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.68.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.70.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.71.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.72.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.73.0/24 | 256 | ARIN | US | 12th Dec 1990 |
| 192.88.74.0/24 | 256 | ARIN | US | 12th Dec 1990 |