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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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.
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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 |
|---|---|---|---|---|
| 198.160.220.0/24 | 256 | ARIN |  US | 9th Sept 1993 |
| 198.160.221.0/24 | 256 | ARIN | US | 9th Sept 1993 |
| 198.160.223.0/24 | 256 | ARIN | US | 9th Sept 1993 |
| 198.160.224.0/24 | 256 | ARIN | US | 9th Sept 1993 |
| 198.160.225.0/24 | 256 | ARIN | US | 9th Sept 1993 |
| 198.160.226.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.160.227.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.160.228.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.160.229.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.160.230.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.160.231.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.160.232.0/22 | 1k | ARIN | US | 10th Sept 1993 |
| 198.160.236.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.160.237.0/24 | 256 | ARIN | US | 30th Apr 2013 |
| 198.160.24.0/23 | 512 | ARIN | US | 4th May 1993 |
| 198.160.244.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.160.246.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.160.247.0/24 | 256 | ARIN | US | 10th Sept 1993 |
| 198.160.251.0/24 | 256 | ARIN | US | 13th Sept 1993 |
| 198.160.254.0/24 | 256 | ARIN | US | 14th Sept 1993 |
| 198.160.4.0/24 | 256 | ARIN | US | 4th May 1993 |
| 198.161.0.0/24 | 256 | ARIN | US | 3rd May 2013 |
| 198.161.80.0/24 | 256 | ARIN | US | 3rd Aug 1993 |
| 198.162.224.0/24 | 256 | ARIN | US | 15th Oct 1993 |
| 198.162.230.0/24 | 256 | ARIN | US | 13th May 2013 |
| 198.162.239.0/24 | 256 | ARIN | US | 29th Mar 1994 |
| 198.162.72.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.73.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.74.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.75.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.76.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.77.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.78.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.79.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.80.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.81.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.82.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.83.0/24 | 256 | ARIN | US | 4th Aug 1993 |
| 198.162.88.0/22 | 1k | ARIN | US | 20th Dec 2024 |
| 198.163.0.0/24 | 256 | ARIN | US | 13th May 2013 |
| 198.163.176.0/23 | 512 | ARIN | US | 8th Jun 1994 |
| 198.163.216.0/24 | 256 | ARIN | US | 5th Sept 2019 |
| 198.163.74.0/24 | 256 | ARIN | US | 26th Nov 1993 |
| 198.167.0.0/24 | 256 | ARIN | US | 2nd Apr 2013 |
| 198.167.129.0/24 | 256 | ARIN | US | 2nd Apr 2013 |
| 198.167.163.0/24 | 256 | ARIN | US | 3rd Apr 2013 |
| 198.168.126.0/24 | 256 | ARIN | US | 9th Apr 2013 |
| 198.168.192.0/24 | 256 | ARIN | US | 15th Oct 1993 |
| 198.168.30.0/24 | 256 | ARIN | US | 4th May 1993 |
| 198.168.43.0/24 | 256 | ARIN | US | 5th Apr 2013 |