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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
26,295 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 23.161.56.0/24 | 256 | ARIN |  US | 30th Aug 2023 |
| 23.161.68.0/24 | 256 | ARIN | US | 15th Jul 2026 |
| 23.161.76.0/24 | 256 | ARIN | US | 15th Jul 2026 |
| 23.161.84.0/24 | 256 | ARIN | US | 16th Jul 2026 |
| 23.162.12.0/24 | 256 | ARIN | US | 31st Jul 2026 |
| 23.162.124.0/24 | 256 | ARIN | US | 14th Aug 2026 |
| 23.162.128.0/24 | 256 | ARIN | US | 28th Apr 2017 |
| 23.162.148.0/24 | 256 | ARIN | US | 18th Aug 2026 |
| 23.162.156.0/24 | 256 | ARIN | US | 17th Aug 2026 |
| 23.162.192.0/24 | 256 | ARIN | US | 27th Dec 2017 |
| 23.162.196.0/24 | 256 | ARIN | US | 24th Aug 2026 |
| 23.162.20.0/24 | 256 | ARIN | US | 5th Aug 2026 |
| 23.162.204.0/24 | 256 | ARIN | US | 19th Aug 2026 |
| 23.162.212.0/24 | 256 | ARIN | US | 25th Aug 2026 |
| 23.162.220.0/24 | 256 | ARIN | US | 25th Aug 2026 |
| 23.162.228.0/24 | 256 | ARIN | US | 25th Aug 2026 |
| 23.162.248.0/24 | 256 | ARIN | US | 5th Oct 2023 |
| 23.162.36.0/24 | 256 | ARIN | US | 7th Aug 2026 |
| 23.162.4.0/24 | 256 | ARIN | US | 3rd Aug 2026 |
| 23.162.44.0/24 | 256 | ARIN | US | 6th Aug 2026 |
| 23.162.52.0/24 | 256 | ARIN | US | 10th Aug 2026 |
| 23.162.68.0/24 | 256 | ARIN | US | 11th Aug 2026 |
| 23.162.8.0/24 | 256 | ARIN | US | 19th Sept 2023 |
| 23.162.92.0/24 | 256 | ARIN | US | 13th Aug 2026 |
| 23.163.104.0/24 | 256 | ARIN | US | 10th Oct 2023 |
| 23.163.12.0/24 | 256 | ARIN | US | 25th Aug 2026 |
| 23.163.145.0/24 | 256 | ARIN | US | 22nd Nov 2022 |
| 23.163.160.0/24 | 256 | ARIN | US | 21st Dec 2018 |
| 23.163.184.0/24 | 256 | ARIN | US | 13th Oct 2023 |
| 23.163.24.0/24 | 256 | ARIN | US | 6th Oct 2023 |
| 23.163.248.0/24 | 256 | ARIN | US | 17th Oct 2023 |
| 23.163.88.0/24 | 256 | ARIN | US | 10th Oct 2023 |
| 23.164.152.0/24 | 256 | ARIN | US | 30th Oct 2023 |
| 23.164.153.0/24 | 256 | ARIN | US | 1st May 2024 |
| 23.165.144.0/24 | 256 | ARIN | US | 4th Oct 2020 |
| 23.165.145.0/24 | 256 | ARIN | US | 16th Feb 2024 |
| 23.165.152.0/24 | 256 | ARIN | US | 14th Nov 2023 |
| 23.165.160.0/24 | 256 | ARIN | US | 4th Jan 2019 |
| 23.165.232.0/24 | 256 | ARIN | US | 16th Nov 2023 |
| 23.165.24.0/24 | 256 | ARIN | US | 7th Nov 2023 |
| 23.165.32.0/24 | 256 | ARIN | US | 4th Jan 2019 |
| 23.165.56.0/24 | 256 | ARIN | US | 13th Nov 2023 |
| 23.165.64.0/24 | 256 | ARIN | US | 5th Jan 2018 |
| 23.165.8.0/24 | 256 | ARIN | US | 6th Nov 2023 |
| 23.166.152.0/24 | 256 | ARIN | US | 22nd Nov 2023 |
| 23.166.192.0/24 | 256 | ARIN | US | 10th Jan 2018 |
| 23.166.200.0/24 | 256 | ARIN | US | 29th Nov 2023 |
| 23.166.226.0/24 | 256 | ARIN | US | 27th Jul 2020 |
| 23.166.64.0/24 | 256 | ARIN | US | 9th Jan 2018 |
| 23.166.8.0/24 | 256 | ARIN | US | 17th Nov 2023 |