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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
26,315 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 198.45.32.0/20 | 4.1k | ARIN |  US | 8th Jan 1993 |
| 198.45.64.0/19 | 8.2k | ARIN | US | 17th Mar 1993 |
| 198.45.96.0/20 | 4.1k | ARIN | US | 17th Mar 1993 |
| 198.46.0.0/21 | 2k | ARIN | US | 12th Jan 1993 |
| 198.46.10.0/23 | 512 | ARIN | US | 1st Jul 2025 |
| 198.46.48.0/20 | 4.1k | ARIN | US | 2nd May 2012 |
| 198.47.0.0/22 | 1k | ARIN | US | 10th Mar 1993 |
| 198.47.30.0/24 | 256 | ARIN | US | 21st Jan 1993 |
| 198.47.4.0/22 | 1k | ARIN | US | 21st Jan 1993 |
| 198.47.89.0/24 | 256 | ARIN | US | 12th Aug 2013 |
| 198.48.16.0/20 | 4.1k | ARIN | US | 12th Jan 1993 |
| 198.48.4.0/22 | 1k | ARIN | US | 27th Jan 1993 |
| 198.49.10.0/24 | 256 | ARIN | US | 27th Jan 1993 |
| 198.49.101.0/24 | 256 | ARIN | US | 8th Feb 1993 |
| 198.49.105.0/24 | 256 | ARIN | US | 8th Feb 1993 |
| 198.49.106.0/24 | 256 | ARIN | US | 8th Feb 1993 |
| 198.49.107.0/24 | 256 | ARIN | US | 8th Feb 1993 |
| 198.49.108.0/24 | 256 | ARIN | US | 8th Feb 1993 |
| 198.49.109.0/24 | 256 | ARIN | US | 8th Feb 1993 |
| 198.49.11.0/24 | 256 | ARIN | US | 27th Jan 1993 |
| 198.49.110.0/24 | 256 | ARIN | US | 8th Feb 1993 |
| 198.49.111.0/24 | 256 | ARIN | US | 8th Feb 1993 |
| 198.49.114.0/24 | 256 | ARIN | US | 9th Feb 1993 |
| 198.49.115.0/24 | 256 | ARIN | US | 9th Feb 1993 |
| 198.49.116.0/23 | 512 | ARIN | US | 9th Feb 1993 |
| 198.49.118.0/24 | 256 | ARIN | US | 9th Feb 1993 |
| 198.49.119.0/24 | 256 | ARIN | US | 9th Feb 1993 |
| 198.49.12.0/24 | 256 | ARIN | US | 27th Jan 1993 |
| 198.49.127.0/24 | 256 | ARIN | US | 9th Feb 1993 |
| 198.49.13.0/24 | 256 | ARIN | US | 1st Jul 2026 |
| 198.49.134.0/24 | 256 | ARIN | US | 9th Feb 1993 |
| 198.49.136.0/24 | 256 | ARIN | US | 10th Feb 1993 |
| 198.49.137.0/24 | 256 | ARIN | US | 10th Feb 1993 |
| 198.49.142.0/24 | 256 | ARIN | US | 10th Feb 1993 |
| 198.49.143.0/24 | 256 | ARIN | US | 25th Mar 2020 |
| 198.49.149.0/24 | 256 | ARIN | US | 18th Feb 1993 |
| 198.49.150.0/24 | 256 | ARIN | US | 18th Feb 1993 |
| 198.49.151.0/24 | 256 | ARIN | US | 18th Feb 1993 |
| 198.49.152.0/23 | 512 | ARIN | US | 19th Feb 1993 |
| 198.49.158.0/24 | 256 | ARIN | US | 19th Feb 1993 |
| 198.49.159.0/24 | 256 | ARIN | US | 19th Feb 1993 |
| 198.49.16.0/22 | 1k | ARIN | US | 27th Jan 1993 |
| 198.49.163.0/24 | 256 | ARIN | US | 19th Feb 1993 |
| 198.49.165.0/24 | 256 | ARIN | US | 22nd Feb 1993 |
| 198.49.166.0/24 | 256 | ARIN | US | 22nd Feb 1993 |
| 198.49.168.0/24 | 256 | ARIN | US | 22nd Feb 1993 |
| 198.49.169.0/24 | 256 | ARIN | US | 22nd Feb 1993 |
| 198.49.170.0/24 | 256 | ARIN | US | 22nd Feb 1993 |
| 198.49.171.0/24 | 256 | ARIN | US | 22nd Feb 1993 |
| 198.49.172.0/24 | 256 | ARIN | US | 22nd Feb 1993 |