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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,124 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.152.162.0/24 | 256 | ARIN |  US | 22nd May 1992 |
| 192.152.163.0/24 | 256 | ARIN | US | 22nd May 1992 |
| 192.152.166.0/24 | 256 | RIPE NCC |  IT | 22nd May 1992 |
| 192.152.167.0/24 | 256 | RIPE NCC |  FR | 22nd May 1992 |
| 192.152.169.0/24 | 256 | ARIN | US | 28th May 1992 |
| 192.152.17.0/24 | 256 | RIPE NCC |  GB | 31st Mar 1992 |
| 192.152.174.0/24 | 256 | RIPE NCC |  PT | 28th May 1992 |
| 192.152.175.0/24 | 256 | ARIN | US | 28th May 1992 |
| 192.152.176.0/24 | 256 | ARIN | US | 28th May 1992 |
| 192.152.177.0/24 | 256 | ARIN | US | 28th May 1992 |
| 192.152.178.0/24 | 256 | ARIN | US | 28th May 1992 |
| 192.152.179.0/24 | 256 | ARIN | US | 28th May 1992 |
| 192.152.182.0/24 | 256 | ARIN | US | 1st Jun 1992 |
| 192.152.184.0/24 | 256 | RIPE NCC | GB | 1st Jun 1992 |
| 192.152.185.0/24 | 256 | RIPE NCC | GB | 1st Jun 1992 |
| 192.152.186.0/24 | 256 | RIPE NCC | GB | 1st Jun 1992 |
| 192.152.187.0/24 | 256 | RIPE NCC | GB | 1st Jun 1992 |
| 192.152.188.0/24 | 256 | ARIN | US | 1st Jun 1992 |
| 192.152.189.0/24 | 256 | ARIN | US | 1st Jun 1992 |
| 192.152.190.0/24 | 256 | ARIN | US | 1st Jun 1992 |
| 192.152.191.0/24 | 256 | ARIN | US | 1st Jun 1992 |
| 192.152.194.0/24 | 256 | ARIN | US | 1st Jun 1992 |
| 192.152.196.0/24 | 256 | ARIN | US | 1st Jun 1992 |
| 192.152.198.0/24 | 256 | ARIN | US | 5th Jun 1992 |
| 192.152.199.0/24 | 256 | ARIN | US | 5th Jun 1992 |
| 192.152.2.0/24 | 256 | ARIN | US | 30th Mar 1992 |
| 192.152.202.0/24 | 256 | ARIN | US | 5th Jun 1992 |
| 192.152.204.0/24 | 256 | ARIN | US | 5th Jun 1992 |
| 192.152.206.0/24 | 256 | ARIN | US | 5th Jun 1992 |
| 192.152.207.0/24 | 256 | ARIN | US | 5th Jun 1992 |
| 192.152.208.0/24 | 256 | ARIN | US | 5th Jun 1992 |
| 192.152.209.0/24 | 256 | ARIN | US | 5th Jun 1992 |
| 192.152.21.0/24 | 256 | ARIN | US | 31st Mar 1992 |
| 192.152.210.0/24 | 256 | ARIN | US | 5th Jun 1992 |
| 192.152.211.0/24 | 256 | ARIN | US | 5th Jun 1992 |
| 192.152.215.0/24 | 256 | ARIN | US | 9th Jun 1992 |
| 192.152.216.0/24 | 256 | ARIN | US | 9th Jun 1992 |
| 192.152.217.0/24 | 256 | ARIN | US | 9th Jun 1992 |
| 192.152.218.0/24 | 256 | ARIN | US | 9th Jun 1992 |
| 192.152.219.0/24 | 256 | ARIN | US | 9th Jun 1992 |
| 192.152.222.0/24 | 256 | ARIN | US | 10th Jun 1992 |
| 192.152.226.0/24 | 256 | ARIN | US | 10th Jun 1992 |
| 192.152.234.0/24 | 256 | ARIN | US | 11th Jun 1992 |
| 192.152.235.0/24 | 256 | ARIN | US | 11th Jun 1992 |
| 192.152.236.0/24 | 256 | ARIN | US | 11th Jun 1992 |
| 192.152.237.0/24 | 256 | ARIN | US | 11th Jun 1992 |
| 192.152.238.0/24 | 256 | ARIN | US | 11th Jun 1992 |
| 192.152.239.0/24 | 256 | ARIN | US | 11th Jun 1992 |
| 192.152.240.0/24 | 256 | ARIN | US | 11th Jun 1992 |
| 192.152.241.0/24 | 256 | RIPE NCC | GB | 11th Jun 1992 |