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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,458 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 204.130.144.0/24 | 256 | ARIN |  US | 15th Nov 1994 |
| 204.130.145.0/24 | 256 | ARIN | US | 15th Nov 1994 |
| 204.130.146.0/24 | 256 | ARIN | US | 15th Nov 1994 |
| 204.130.148.0/24 | 256 | ARIN | US | 15th Nov 1994 |
| 204.130.149.0/24 | 256 | ARIN | US | 15th Nov 1994 |
| 204.130.150.0/24 | 256 | ARIN | US | 15th Nov 1994 |
| 204.130.152.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.153.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.156.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.157.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.159.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.16.0/20 | 4.1k | ARIN | US | 24th Aug 1994 |
| 204.130.160.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.161.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.162.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.163.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.164.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.165.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.166.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.168.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.169.0/24 | 256 | ARIN | US | 16th Nov 1994 |
| 204.130.170.0/24 | 256 | ARIN | US | 17th Nov 1994 |
| 204.130.171.0/24 | 256 | ARIN | US | 17th Nov 1994 |
| 204.130.173.0/24 | 256 | ARIN | US | 17th Nov 1994 |
| 204.130.174.0/24 | 256 | ARIN | US | 17th Nov 1994 |
| 204.130.177.0/24 | 256 | ARIN | US | 23rd Nov 1994 |
| 204.130.178.0/24 | 256 | ARIN | US | 28th Nov 1994 |
| 204.130.179.0/24 | 256 | ARIN | US | 28th Nov 1994 |
| 204.130.180.0/24 | 256 | ARIN | US | 28th Nov 1994 |
| 204.130.181.0/24 | 256 | ARIN | US | 28th Nov 1994 |
| 204.130.182.0/24 | 256 | ARIN | US | 28th Nov 1994 |
| 204.130.183.0/24 | 256 | ARIN | US | 29th Nov 1994 |
| 204.130.184.0/24 | 256 | ARIN | US | 29th Nov 1994 |
| 204.130.185.0/24 | 256 | ARIN | US | 29th Nov 1994 |
| 204.130.186.0/24 | 256 | ARIN | US | 29th Nov 1994 |
| 204.130.188.0/24 | 256 | ARIN | US | 29th Nov 1994 |
| 204.130.189.0/24 | 256 | ARIN | US | 29th Nov 1994 |
| 204.130.192.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.193.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.194.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.195.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.196.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.197.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.198.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.199.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.201.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.203.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.204.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.205.0/24 | 256 | ARIN | US | 30th Nov 1994 |
| 204.130.206.0/24 | 256 | ARIN | US | 2nd Dec 1994 |