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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 the most unannounced blocks, largest first.
Unannounced blocks
85,041 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 164.57.0.0/17 | 32.8k | ARIN |  US | 5th Dec 1992 |
| 164.57.128.0/18 | 16.4k | ARIN | US | 5th Dec 1992 |
| 164.57.224.0/19 | 8.2k | ARIN | US | 5th Dec 1992 |
| 164.6.0.0/16 | 65.5k | RIPE NCC |  GB | 25th Sept 1992 |
| 164.68.0.0/18 | 16.4k | ARIN | US | 17th Dec 1992 |
| 164.7.0.0/16 | 65.5k | RIPE NCC |  FR | 7th Oct 1993 |
| 164.72.0.0/16 | 65.5k | ARIN | US | 16th Nov 1992 |
| 164.79.0.0/16 | 65.5k | ARIN | US | 29th Dec 1992 |
| 164.84.0.0/16 | 65.5k | ARIN | US | 11th Jan 1993 |
| 164.89.0.0/16 | 65.5k | ARIN | US | 21st Jan 1993 |
| 164.91.0.0/16 | 65.5k | ARIN | US | 25th Jan 1993 |
| 164.93.0.0/17 | 32.8k | ARIN | US | 11th Jul 2023 |
| 164.93.128.0/17 | 32.8k | RIPE NCC | GB | 12th Nov 2013 |
| 164.96.0.0/16 | 65.5k | LACNIC |  CL | 29th Jan 1993 |
| 164.98.0.0/16 | 65.5k | LACNIC | CL | 2nd Feb 1993 |
| 165.100.160.0/20 | 4.1k | ARIN | US | 26th Jun 2024 |
| 165.101.0.0/22 | 1k | APNIC |  JP | 11th May 1993 |
| 165.101.138.0/23 | 512 | APNIC |  IN | 4th Jul 2025 |
| 165.101.144.0/23 | 512 | APNIC |  CN | 7th Jul 2025 |
| 165.101.158.0/23 | 512 | APNIC |  VN | 9th Jul 2025 |
| 165.101.163.0/24 | 256 | APNIC | IN | 10th Jul 2025 |
| 165.101.170.0/23 | 512 | APNIC | CN | 10th Jul 2025 |
| 165.101.178.0/24 | 256 | APNIC |  AU | 10th Jul 2025 |
| 165.101.202.0/23 | 512 | APNIC |  ID | 15th Jul 2025 |
| 165.101.244.0/23 | 512 | APNIC | CN | 22nd Jul 2025 |
| 165.101.31.0/24 | 256 | APNIC | ID | 19th Jun 2025 |
| 165.101.34.0/23 | 512 | APNIC | VN | 19th Jun 2025 |
| 165.101.36.0/23 | 512 | APNIC | VN | 19th Jun 2025 |
| 165.101.4.0/23 | 512 | APNIC | CN | 13th Jun 2025 |
| 165.101.44.0/23 | 512 | APNIC | VN | 19th Jun 2025 |
| 165.101.48.0/24 | 256 | APNIC |  MM | 20th Jun 2025 |
| 165.101.59.0/24 | 256 | APNIC | IN | 25th Jun 2025 |
| 165.101.66.0/23 | 512 | APNIC | CN | 25th Jun 2025 |
| 165.102.0.0/16 | 65.5k | APNIC | JP | 11th May 1993 |
| 165.105.0.0/16 | 65.5k | ARIN | US | 12th May 1993 |
| 165.114.0.0/16 | 65.5k | RIPE NCC |  NL | 22nd Aug 2007 |
| 165.116.0.0/16 | 65.5k | ARIN | US | 20th May 1993 |
| 165.126.0.0/16 | 65.5k | ARIN | US | 1st Jun 1993 |
| 165.135.0.0/16 | 65.5k | ARIN | US | 9th Jun 1993 |
| 165.136.0.0/16 | 65.5k | ARIN | US | 9th Jun 1993 |
| 165.140.0.0/22 | 1k | ARIN | US | 7th Jan 2022 |
| 165.140.104.0/24 | 256 | ARIN | US | 11th Apr 2024 |
| 165.140.107.0/24 | 256 | ARIN |  CA | 7th Oct 2021 |
| 165.140.136.0/22 | 1k | ARIN | US | 2nd Dec 2021 |
| 165.140.142.0/24 | 256 | ARIN | CA | 5th Oct 2021 |
| 165.140.188.0/24 | 256 | ARIN | US | 4th Nov 2021 |
| 165.140.4.0/22 | 1k | ARIN | US | 6th Jan 2022 |
| 165.140.52.0/24 | 256 | ARIN | US | 23rd Dec 2024 |
| 165.140.57.0/24 | 256 | ARIN | US | 2nd Apr 2026 |
| 165.140.80.0/22 | 1k | ARIN | US | 6th Jan 2022 |