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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
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Countries with unannounced space registered through ARIN, largest first.
Unannounced blocks registered through ARIN
30,479 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 204.79.136.0/24 | 256 | ARIN |  FR | 14th Dec 1994 |
| 204.79.143.0/24 | 256 | ARIN |  US | 14th Dec 1994 |
| 204.79.144.0/23 | 512 | ARIN | US | 14th Dec 1994 |
| 204.79.146.0/24 | 256 | ARIN |  SE | 14th Dec 1994 |
| 204.79.148.0/24 | 256 | ARIN |  DE | 14th Dec 1994 |
| 204.79.149.0/24 | 256 | ARIN | DE | 14th Dec 1994 |
| 204.79.150.0/23 | 512 | ARIN | US | 14th Dec 1994 |
| 204.79.152.0/22 | 1k | ARIN | US | 14th Dec 1994 |
| 204.79.156.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.157.0/24 | 256 | ARIN |  JP | 14th Dec 1994 |
| 204.79.158.0/24 | 256 | ARIN | JP | 14th Dec 1994 |
| 204.79.159.0/24 | 256 | ARIN |  NO | 14th Dec 1994 |
| 204.79.160.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.161.0/24 | 256 | ARIN |  CH | 14th Dec 1994 |
| 204.79.162.0/23 | 512 | ARIN | CH | 14th Dec 1994 |
| 204.79.164.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.165.0/24 | 256 | ARIN |  CA | 14th Dec 1994 |
| 204.79.168.0/24 | 256 | ARIN | DE | 14th Dec 1994 |
| 204.79.169.0/24 | 256 | ARIN |  HK | 14th Dec 1994 |
| 204.79.170.0/24 | 256 | ARIN |  BE | 14th Dec 1994 |
| 204.79.171.0/24 | 256 | ARIN | DE | 14th Dec 1994 |
| 204.79.173.0/24 | 256 | ARIN | FR | 14th Dec 1994 |
| 204.79.174.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.175.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.176.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.177.0/24 | 256 | ARIN | DE | 14th Dec 1994 |
| 204.79.178.0/24 | 256 | ARIN | DE | 14th Dec 1994 |
| 204.79.181.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.184.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.185.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.186.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.187.0/24 | 256 | ARIN | DE | 14th Dec 1994 |
| 204.79.188.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.189.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.190.0/24 | 256 | ARIN | US | 14th Dec 1994 |
| 204.79.191.0/24 | 256 | ARIN | SE | 14th Dec 1994 |
| 204.79.194.0/24 | 256 | ARIN |  GB | 15th Dec 1994 |
| 204.79.198.0/24 | 256 | ARIN | GB | 15th Dec 1994 |
| 204.79.199.0/24 | 256 | ARIN | DE | 15th Dec 1994 |
| 204.79.200.0/24 | 256 | ARIN | DE | 15th Dec 1994 |
| 204.79.201.0/24 | 256 | ARIN | US | 19th Dec 1994 |
| 204.79.202.0/24 | 256 | ARIN | US | 19th Dec 1994 |
| 204.79.203.0/24 | 256 | ARIN | US | 19th Dec 1994 |
| 204.79.204.0/24 | 256 | ARIN | BE | 19th Dec 1994 |
| 204.79.205.0/24 | 256 | ARIN | US | 19th Dec 1994 |
| 204.79.206.0/24 | 256 | ARIN | US | 19th Dec 1994 |
| 204.79.207.0/24 | 256 | ARIN | GB | 19th Dec 1994 |
| 204.79.208.0/23 | 512 | ARIN | FR | 19th Dec 1994 |
| 204.79.210.0/24 | 256 | ARIN | FR | 19th Dec 1994 |
| 204.79.211.0/24 | 256 | ARIN | GB | 19th Dec 1994 |