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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
Browse by country
Countries with the most unannounced blocks, largest first.
Unannounced blocks
84,968 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 141.193.136.0/24 | 256 | ARIN |  US | 12th Apr 2021 |
| 141.193.139.0/24 | 256 | ARIN | US | 5th Apr 2021 |
| 141.193.144.0/22 | 1k | ARIN | US | 6th Aug 2018 |
| 141.193.148.0/24 | 256 | ARIN | US | 6th Jul 2020 |
| 141.193.150.0/24 | 256 | ARIN | US | 14th Sept 2020 |
| 141.193.18.0/23 | 512 | ARIN | US | 26th May 2017 |
| 141.193.212.0/24 | 256 | ARIN | US | 1st Jun 2020 |
| 141.193.224.0/24 | 256 | ARIN | US | 19th Feb 2020 |
| 141.193.227.0/24 | 256 | ARIN | US | 8th May 2019 |
| 141.193.232.0/24 | 256 | ARIN | US | 12th Feb 2019 |
| 141.193.25.0/24 | 256 | ARIN | US | 18th Jul 2017 |
| 141.193.26.0/24 | 256 | ARIN | US | 1st Sept 2017 |
| 141.193.70.0/24 | 256 | ARIN | US | 9th Jun 2021 |
| 141.195.112.0/22 | 1k | ARIN |  TH | 19th Dec 2023 |
| 141.204.0.0/16 | 65.5k | ARIN | US | 3rd Aug 1990 |
| 141.205.0.0/16 | 65.5k | ARIN | US | 3rd Aug 1990 |
| 141.206.0.0/17 | 32.8k | ARIN | US | 16th Oct 1992 |
| 141.206.128.0/20 | 4.1k | ARIN | US | 16th Oct 1992 |
| 141.206.160.0/19 | 8.2k | ARIN | US | 16th Oct 1992 |
| 141.224.112.0/20 | 4.1k | ARIN | US | 14th Jun 2024 |
| 141.226.132.0/24 | 256 | RIPE NCC |  IL | 5th Aug 1990 |
| 141.226.133.0/24 | 256 | RIPE NCC | IL | 5th Aug 1990 |
| 141.226.134.0/24 | 256 | RIPE NCC | IL | 5th Aug 1990 |
| 141.226.135.0/24 | 256 | RIPE NCC |  DE | 5th Aug 1990 |
| 141.226.138.0/24 | 256 | ARIN | US | 6th Jul 2017 |
| 141.226.139.0/24 | 256 | RIPE NCC | IL | 5th Aug 1990 |
| 141.226.250.0/23 | 512 | RIPE NCC | IL | 5th Aug 1990 |
| 141.226.84.0/23 | 512 | RIPE NCC |  BG | 5th Aug 1990 |
| 141.226.86.0/24 | 256 | RIPE NCC | BG | 5th Aug 1990 |
| 141.240.0.0/16 | 65.5k | ARIN | US | 10th Aug 1990 |
| 141.245.0.0/16 | 65.5k | RIPE NCC |  GB | 10th Aug 1990 |
| 141.247.0.0/16 | 65.5k | ARIN | US | 21st Jun 1994 |
| 141.251.0.0/16 | 65.5k | ARIN | US | 22nd Jun 2011 |
| 141.8.216.0/21 | 2k | RIPE NCC | GB | 23rd Jun 2011 |
| 141.97.0.0/16 | 65.5k | RIPE NCC | GB | 24th Feb 1993 |
| 141.98.92.0/22 | 1k | RIPE NCC |  BZ | 11th Jan 2019 |
| 141.98.96.0/22 | 1k | RIPE NCC |  NL | 11th Jan 2019 |
| 142.0.16.0/20 | 4.1k | ARIN |  CA | 29th May 2012 |
| 142.0.224.0/20 | 4.1k | ARIN |  JM | 8th Jan 2024 |
| 142.0.68.0/22 | 1k | ARIN | US | 26th Jun 2024 |
| 142.10.0.0/16 | 65.5k | ARIN | CA | 30th Nov 1990 |
| 142.101.0.0/16 | 65.5k | ARIN | CA | 27th Jan 1992 |
| 142.102.0.0/16 | 65.5k | ARIN | CA | 27th Jan 1992 |
| 142.11.128.0/18 | 16.4k | ARIN | US | 19th Jun 2012 |
| 142.11.64.0/18 | 16.4k | ARIN | US | 19th Jun 2012 |
| 142.128.0.0/16 | 65.5k | ARIN | CA | 4th Mar 1992 |
| 142.130.0.0/16 | 65.5k | ARIN | CA | 8th Apr 1993 |
| 142.135.0.0/16 | 65.5k | ARIN | CA | 23rd Apr 1992 |
| 142.138.0.0/16 | 65.5k | ARIN | CA | 13th May 1992 |
| 142.147.100.0/24 | 256 | ARIN | CA | 5th Jun 2014 |