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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
26,302 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 198.184.219.0/24 | 256 | ARIN |  US | 29th Dec 1993 |
| 198.184.221.0/24 | 256 | ARIN | US | 29th Dec 1993 |
| 198.184.222.0/24 | 256 | ARIN | US | 6th Jul 2026 |
| 198.184.223.0/24 | 256 | ARIN | US | 29th Dec 1993 |
| 198.184.224.0/24 | 256 | ARIN | US | 29th Dec 1993 |
| 198.184.225.0/24 | 256 | ARIN | US | 29th Dec 1993 |
| 198.184.226.0/24 | 256 | ARIN | US | 29th Dec 1993 |
| 198.184.228.0/23 | 512 | ARIN | US | 29th Dec 1993 |
| 198.184.230.0/24 | 256 | ARIN | US | 29th Dec 1993 |
| 198.184.236.0/22 | 1k | ARIN | US | 29th Dec 1993 |
| 198.184.24.0/23 | 512 | ARIN | US | 18th Jun 1993 |
| 198.184.240.0/24 | 256 | ARIN | US | 29th Dec 1993 |
| 198.184.241.0/24 | 256 | ARIN | US | 29th Dec 1993 |
| 198.184.242.0/23 | 512 | ARIN | US | 29th Dec 1993 |
| 198.184.244.0/24 | 256 | ARIN | US | 29th Dec 1993 |
| 198.184.48.0/21 | 2k | ARIN | US | 8th Jul 1993 |
| 198.184.60.0/23 | 512 | ARIN | US | 8th Jul 1993 |
| 198.184.8.0/22 | 1k | ARIN | US | 9th Feb 1994 |
| 198.185.128.0/24 | 256 | ARIN | US | 29th Dec 1993 |
| 198.185.130.0/24 | 256 | ARIN | US | 4th Jan 1994 |
| 198.185.131.0/24 | 256 | ARIN | US | 4th Jan 1994 |
| 198.185.132.0/24 | 256 | ARIN | US | 4th Jan 1994 |
| 198.185.138.0/24 | 256 | ARIN | US | 4th Jan 1994 |
| 198.185.139.0/24 | 256 | ARIN | US | 7th May 1996 |
| 198.185.141.0/24 | 256 | ARIN | US | 5th Jan 1994 |
| 198.185.142.0/24 | 256 | ARIN | US | 5th Jan 1994 |
| 198.185.143.0/24 | 256 | ARIN | US | 5th Jan 1994 |
| 198.185.144.0/24 | 256 | ARIN | US | 5th Jan 1994 |
| 198.185.152.0/24 | 256 | ARIN | US | 6th Jan 1994 |
| 198.185.153.0/24 | 256 | ARIN | US | 6th Jan 1994 |
| 198.185.155.0/24 | 256 | ARIN | US | 11th Jan 1994 |
| 198.185.156.0/23 | 512 | ARIN | US | 11th Jan 1994 |
| 198.185.158.0/24 | 256 | ARIN | US | 11th Jan 1994 |
| 198.185.167.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 198.185.182.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 198.185.183.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 198.185.184.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 198.185.185.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 198.185.186.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 198.185.187.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 198.185.192.0/23 | 512 | ARIN | US | 13th Jan 1994 |
| 198.185.194.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 198.185.195.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 198.185.196.0/23 | 512 | ARIN | US | 21st Jan 1994 |
| 198.185.198.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 198.185.199.0/24 | 256 | ARIN | US | 22nd Jan 1994 |
| 198.185.200.0/24 | 256 | ARIN | US | 22nd Jan 1994 |
| 198.185.202.0/24 | 256 | ARIN | US | 22nd Jan 1994 |
| 198.185.203.0/24 | 256 | ARIN | US | 22nd Jan 1994 |
| 198.185.204.0/24 | 256 | ARIN | US | 22nd Jan 1994 |