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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 in United States
26,300 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 204.80.152.0/24 | 256 | ARIN |  US | 11th Jan 1995 |
| 204.80.153.0/24 | 256 | ARIN | US | 11th Jan 1995 |
| 204.80.154.0/24 | 256 | ARIN | US | 14th Jan 1995 |
| 204.80.155.0/24 | 256 | ARIN | US | 15th Jan 1995 |
| 204.80.156.0/24 | 256 | ARIN | US | 15th Jan 1995 |
| 204.80.158.0/24 | 256 | ARIN | US | 15th Jan 1995 |
| 204.80.16.0/20 | 4.1k | ARIN | US | 19th Jul 1994 |
| 204.80.160.0/24 | 256 | ARIN | US | 17th Jan 1995 |
| 204.80.162.0/24 | 256 | ARIN | US | 19th Jan 1995 |
| 204.80.163.0/24 | 256 | ARIN | US | 21st Mar 1996 |
| 204.80.165.0/24 | 256 | ARIN | US | 24th Jan 1995 |
| 204.80.166.0/24 | 256 | ARIN | US | 24th Jan 1995 |
| 204.80.167.0/24 | 256 | ARIN | US | 24th Jan 1995 |
| 204.80.168.0/24 | 256 | ARIN | US | 24th Jan 1995 |
| 204.80.169.0/24 | 256 | ARIN | US | 24th Jan 1995 |
| 204.80.170.0/24 | 256 | ARIN | US | 24th Jan 1995 |
| 204.80.171.0/24 | 256 | ARIN | US | 24th Jan 1995 |
| 204.80.172.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.173.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.174.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.175.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.176.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.177.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.178.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.179.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.181.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.182.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.184.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.185.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.186.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.188.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.189.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.190.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.192.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.193.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.195.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.196.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.197.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.198.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.199.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.200.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.201.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.202.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.203.0/24 | 256 | ARIN | US | 25th Jan 1995 |
| 204.80.204.0/24 | 256 | ARIN | US | 7th Feb 1995 |
| 204.80.205.0/24 | 256 | ARIN | US | 7th Feb 1995 |
| 204.80.206.0/24 | 256 | ARIN | US | 7th Feb 1995 |
| 204.80.207.0/24 | 256 | ARIN | US | 7th Feb 1995 |
| 204.80.208.0/24 | 256 | ARIN | US | 7th Feb 1995 |
| 204.80.209.0/24 | 256 | ARIN | US | 7th Feb 1995 |