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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 198.17.63.0/24 | 256 | ARIN |  US | 16th Dec 1992 |
| 198.17.65.0/24 | 256 | ARIN | US | 16th Dec 1992 |
| 198.17.67.0/24 | 256 | ARIN | US | 22nd Sept 2021 |
| 198.17.68.0/24 | 256 | ARIN | US | 22nd Sept 2021 |
| 198.17.69.0/24 | 256 | ARIN | US | 16th Dec 1992 |
| 198.17.71.0/24 | 256 | ARIN | US | 18th Dec 1992 |
| 198.17.72.0/24 | 256 | ARIN | US | 18th Dec 1992 |
| 198.17.73.0/24 | 256 | ARIN | US | 18th Dec 1992 |
| 198.17.74.0/24 | 256 | ARIN | US | 18th Dec 1992 |
| 198.17.75.0/24 | 256 | ARIN | US | 18th Dec 1992 |
| 198.17.78.0/24 | 256 | ARIN | US | 18th Dec 1992 |
| 198.17.8.0/24 | 256 | ARIN | US | 3rd Dec 1992 |
| 198.17.80.0/24 | 256 | ARIN | US | 18th Dec 1992 |
| 198.17.83.0/24 | 256 | ARIN | US | 21st Dec 1992 |
| 198.17.85.0/24 | 256 | ARIN | US | 21st Dec 1992 |
| 198.17.87.0/24 | 256 | ARIN | US | 21st Dec 1992 |
| 198.17.88.0/24 | 256 | ARIN | US | 21st Dec 1992 |
| 198.17.89.0/24 | 256 | ARIN | US | 15th Apr 2013 |
| 198.17.9.0/24 | 256 | ARIN | US | 3rd Dec 1992 |
| 198.17.90.0/24 | 256 | ARIN | US | 21st Dec 1992 |
| 198.17.91.0/24 | 256 | ARIN | US | 21st Dec 1992 |
| 198.17.93.0/24 | 256 | ARIN | US | 21st Dec 1992 |
| 198.17.94.0/24 | 256 | ARIN | US | 21st Dec 1992 |
| 198.17.97.0/24 | 256 | ARIN | US | 21st Dec 1992 |
| 198.17.98.0/24 | 256 | ARIN | US | 21st Dec 1992 |
| 198.175.0.0/22 | 1k | ARIN | US | 11th May 1993 |
| 198.175.120.0/22 | 1k | ARIN | US | 12th May 1993 |
| 198.175.128.0/21 | 2k | ARIN | US | 29th Jun 1993 |
| 198.175.136.0/23 | 512 | ARIN | US | 29th Jun 1993 |
| 198.175.138.0/23 | 512 | ARIN | US | 29th Jun 1993 |
| 198.175.142.0/24 | 256 | ARIN | US | 22nd Nov 1993 |
| 198.175.143.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.144.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.145.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.146.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.147.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.148.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.149.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.156.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.157.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.158.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.159.0/24 | 256 | ARIN | US | 30th Jun 1993 |
| 198.175.16.0/22 | 1k | ARIN | US | 31st Mar 2021 |
| 198.175.160.0/24 | 256 | ARIN | US | 1st Jul 1993 |
| 198.175.162.0/24 | 256 | ARIN | US | 1st Jul 1993 |
| 198.175.163.0/24 | 256 | ARIN | US | 1st Jul 1993 |
| 198.175.164.0/24 | 256 | ARIN | US | 1st Jul 1993 |
| 198.175.165.0/24 | 256 | ARIN | US | 1st Jul 1993 |
| 198.175.171.0/24 | 256 | ARIN | US | 1st Jul 1993 |
| 198.175.172.0/24 | 256 | ARIN | US | 27th Nov 2024 |