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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 199.254.138.0/24 | 256 | ARIN |  US | 13th Oct 1994 |
| 199.254.139.0/24 | 256 | ARIN | US | 13th Oct 1994 |
| 199.254.140.0/24 | 256 | ARIN | US | 13th Oct 1994 |
| 199.254.142.0/24 | 256 | ARIN | US | 13th Oct 1994 |
| 199.254.143.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.144.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.145.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.146.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.147.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.148.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.150.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.151.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.152.0/24 | 256 | ARIN |  CA | 14th Oct 1994 |
| 199.254.153.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.154.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.155.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.159.0/24 | 256 | ARIN | US | 14th Oct 1994 |
| 199.254.161.0/24 | 256 | ARIN | US | 19th Oct 1994 |
| 199.254.162.0/24 | 256 | ARIN | US | 19th Oct 1994 |
| 199.254.163.0/24 | 256 | ARIN | US | 19th Oct 1994 |
| 199.254.164.0/24 | 256 | ARIN | US | 19th Oct 1994 |
| 199.254.166.0/24 | 256 | ARIN | US | 20th Oct 1994 |
| 199.254.167.0/24 | 256 | ARIN | US | 20th Oct 1994 |
| 199.254.169.0/24 | 256 | ARIN | US | 20th Oct 1994 |
| 199.254.172.0/24 | 256 | ARIN | US | 21st Oct 1994 |
| 199.254.173.0/24 | 256 | ARIN | US | 21st Oct 1994 |
| 199.254.174.0/24 | 256 | ARIN | US | 21st Oct 1994 |
| 199.254.175.0/24 | 256 | ARIN | US | 21st Oct 1994 |
| 199.254.178.0/24 | 256 | ARIN | US | 21st Oct 1994 |
| 199.254.179.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.180.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.181.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.182.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.183.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.184.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.185.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.186.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.187.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.188.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.189.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.190.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.191.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.192.0/24 | 256 | ARIN | US | 24th Oct 1994 |
| 199.254.193.0/24 | 256 | ARIN | US | 25th Oct 1994 |
| 199.254.194.0/24 | 256 | ARIN | US | 25th Oct 1994 |
| 199.254.195.0/24 | 256 | ARIN | US | 25th Oct 1994 |
| 199.254.196.0/24 | 256 | ARIN | US | 25th Oct 1994 |
| 199.254.198.0/24 | 256 | ARIN | US | 26th Oct 1994 |
| 199.254.200.0/24 | 256 | ARIN | US | 26th Oct 1994 |
| 199.254.203.0/24 | 256 | ARIN | US | 26th Oct 1994 |