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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
84,818 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 81.172.66.0/24 | 256 | RIPE NCC |  US | 14th Jan 2003 |
| 81.172.67.0/24 | 256 | RIPE NCC |  DE | 14th Jan 2003 |
| 81.173.116.0/22 | 1k | RIPE NCC |  GB | 19th Feb 2003 |
| 81.173.120.0/22 | 1k | RIPE NCC | GB | 19th Feb 2003 |
| 81.173.5.0/24 | 256 | RIPE NCC |  NL | 19th Feb 2003 |
| 81.199.144.0/23 | 512 | ARIN | US | 13th Jan 2022 |
| 81.199.36.0/22 | 1k | ARIN | US | 13th Jan 2022 |
| 81.20.0.0/20 | 4.1k | RIPE NCC | GB | 19th May 2009 |
| 81.201.64.0/20 | 4.1k | RIPE NCC |  RU | 10th Oct 2002 |
| 81.203.0.0/16 | 65.5k | APNIC |  JP | 12th Nov 2002 |
| 81.208.144.0/20 | 4.1k | RIPE NCC |  SE | 8th Oct 2002 |
| 81.21.208.0/20 | 4.1k | RIPE NCC | SE | 18th Jan 2006 |
| 81.21.64.0/20 | 4.1k | RIPE NCC | DE | 15th Feb 2002 |
| 81.22.112.0/20 | 4.1k | RIPE NCC |  SA | 23rd Jan 2006 |
| 81.22.194.0/23 | 512 | RIPE NCC | RU | 25th Feb 2002 |
| 81.22.228.0/22 | 1k | RIPE NCC |  HU | 11th Sept 2018 |
| 81.22.236.0/22 | 1k | RIPE NCC |  CZ | 11th Sept 2018 |
| 81.22.64.0/19 | 8.2k | AFRINIC |  CI | 28th Feb 2020 |
| 81.23.128.0/20 | 4.1k | RIPE NCC |  DK | 13th Aug 2010 |
| 81.24.176.0/20 | 4.1k | RIPE NCC | RU | 14th Oct 2010 |
| 81.27.0.0/20 | 4.1k | RIPE NCC | SE | 8th Apr 2002 |
| 81.27.224.0/22 | 1k | RIPE NCC | DE | 15th Apr 2002 |
| 81.27.239.0/24 | 256 | RIPE NCC | DE | 15th Apr 2002 |
| 81.27.65.0/24 | 256 | RIPE NCC |  KZ | 11th Apr 2002 |
| 81.27.85.0/24 | 256 | RIPE NCC | GB | 11th Apr 2002 |
| 81.28.0.0/22 | 1k | RIPE NCC | RU | 16th Apr 2002 |
| 81.28.240.0/22 | 1k | RIPE NCC |  ES | 17th Aug 2018 |
| 81.28.64.0/20 | 4.1k | RIPE NCC | DE | 17th Apr 2002 |
| 81.29.0.0/20 | 4.1k | RIPE NCC |  CW | 24th Apr 2002 |
| 81.30.102.0/24 | 256 | RIPE NCC |  FR | 18th Jun 2024 |
| 81.30.106.0/24 | 256 | RIPE NCC |  MH | 21st Jun 2024 |
| 81.30.111.0/24 | 256 | RIPE NCC | DE | 25th Jun 2024 |
| 81.30.99.0/24 | 256 | RIPE NCC | ES | 18th Jun 2024 |
| 81.31.216.0/21 | 2k | RIPE NCC | NL | 10th Aug 2012 |
| 81.85.112.0/20 | 4.1k | RIPE NCC | NL | 30th May 2002 |
| 81.85.68.0/22 | 1k | RIPE NCC | GB | 30th May 2002 |
| 81.89.144.0/20 | 4.1k | RIPE NCC | SE | 16th Sept 2009 |
| 81.91.192.0/20 | 4.1k | RIPE NCC | GB | 22nd Jul 2002 |
| 81.92.244.0/22 | 1k | ARIN | US | 4th Apr 2022 |
| 81.94.34.0/24 | 256 | RIPE NCC | RU | 9th Aug 2002 |
| 81.94.40.0/24 | 256 | RIPE NCC | RU | 9th Aug 2002 |
| 81.94.96.0/20 | 4.1k | RIPE NCC | US | 14th Aug 2002 |
| 81.95.208.0/20 | 4.1k | RIPE NCC | RU | 31st May 2006 |
| 81.95.54.0/23 | 512 | RIPE NCC | DE | 19th May 2006 |
| 82.115.15.0/24 | 256 | RIPE NCC |  BZ | 6th Jan 2004 |
| 82.115.192.0/20 | 4.1k | RIPE NCC | SE | 19th Jan 2004 |
| 82.115.224.0/20 | 4.1k | RIPE NCC | SE | 19th Jan 2004 |
| 82.115.240.0/21 | 2k | RIPE NCC | SE | 19th Jan 2004 |
| 82.115.248.0/22 | 1k | RIPE NCC | SE | 19th Jan 2004 |
| 82.115.252.0/24 | 256 | RIPE NCC | GB | 19th Jan 2004 |