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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 198.177.175.0/24 | 256 | ARIN |  US | 12th Oct 1993 |
| 198.177.176.0/22 | 1k | ARIN | US | 12th Oct 1993 |
| 198.177.180.0/24 | 256 | ARIN | US | 12th Oct 1993 |
| 198.177.182.0/24 | 256 | ARIN | US | 12th Oct 1993 |
| 198.177.183.0/24 | 256 | ARIN | US | 12th Oct 1993 |
| 198.177.186.0/23 | 512 | ARIN | US | 14th Oct 1993 |
| 198.177.188.0/23 | 512 | ARIN | US | 14th Oct 1993 |
| 198.177.190.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.198.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.200.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.201.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.202.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.203.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.204.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.205.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.206.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.208.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.209.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.210.0/24 | 256 | ARIN | US | 14th Oct 1993 |
| 198.177.211.0/24 | 256 | ARIN | US | 15th Oct 1993 |
| 198.177.212.0/24 | 256 | ARIN | US | 15th Oct 1993 |
| 198.177.213.0/24 | 256 | ARIN | US | 15th Oct 1993 |
| 198.177.214.0/24 | 256 | ARIN | US | 15th Oct 1993 |
| 198.177.215.0/24 | 256 | ARIN | US | 15th Oct 1993 |
| 198.177.216.0/24 | 256 | ARIN | US | 15th Oct 1993 |
| 198.177.218.0/24 | 256 | ARIN | US | 18th Oct 1993 |
| 198.177.219.0/24 | 256 | ARIN | US | 18th Oct 1993 |
| 198.177.220.0/23 | 512 | ARIN | US | 18th Oct 1993 |
| 198.177.222.0/24 | 256 | ARIN | US | 18th Oct 1993 |
| 198.177.223.0/24 | 256 | ARIN | US | 18th Oct 1993 |
| 198.177.224.0/24 | 256 | ARIN | US | 18th Oct 1993 |
| 198.177.226.0/24 | 256 | ARIN | US | 19th Oct 1993 |
| 198.177.228.0/24 | 256 | ARIN | US | 19th Oct 1993 |
| 198.177.229.0/24 | 256 | ARIN | US | 19th Oct 1993 |
| 198.177.231.0/24 | 256 | ARIN | US | 19th Oct 1993 |
| 198.177.233.0/24 | 256 | ARIN | US | 19th Oct 1993 |
| 198.177.234.0/24 | 256 | ARIN | US | 19th Oct 1993 |
| 198.177.235.0/24 | 256 | ARIN | US | 19th Oct 1993 |
| 198.177.236.0/24 | 256 | ARIN | US | 19th Oct 1993 |
| 198.177.237.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.177.238.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.177.239.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.177.240.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.177.241.0/24 | 256 | ARIN | US | 6th May 2022 |
| 198.177.242.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.177.243.0/24 | 256 | ARIN | US | 20th Oct 1993 |
| 198.177.244.0/22 | 1k | ARIN | US | 12th Feb 1997 |
| 198.177.248.0/23 | 512 | ARIN | US | 6th Oct 1993 |
| 198.177.250.0/24 | 256 | ARIN | US | 6th Oct 1993 |
| 198.177.32.0/20 | 4.1k | ARIN | US | 26th May 1993 |