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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,356 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 206.71.0.0/21 | 2k | ARIN |  US | 25th Jul 1995 |
| 206.71.10.0/24 | 256 | ARIN | US | 8th Feb 2017 |
| 206.71.11.0/24 | 256 | ARIN |  CA | 1st Mar 2017 |
| 206.71.12.0/24 | 256 | ARIN | US | 24th Mar 2017 |
| 206.71.128.0/21 | 2k | ARIN | US | 28th Jul 1995 |
| 206.71.13.0/24 | 256 | ARIN | US | 20th Jun 2017 |
| 206.71.136.0/24 | 256 | ARIN | US | 10th Aug 2017 |
| 206.71.137.0/24 | 256 | ARIN | CA | 29th Aug 2017 |
| 206.71.138.0/24 | 256 | ARIN | US | 12th Sept 2017 |
| 206.71.139.0/24 | 256 | ARIN | US | 14th Sept 2017 |
| 206.71.14.0/24 | 256 | ARIN | US | 20th Jun 2017 |
| 206.71.140.0/24 | 256 | ARIN | US | 23rd Oct 2017 |
| 206.71.141.0/24 | 256 | ARIN | US | 7th Nov 2017 |
| 206.71.142.0/24 | 256 | ARIN | US | 27th Nov 2017 |
| 206.71.143.0/24 | 256 | ARIN | US | 27th Nov 2017 |
| 206.71.15.0/24 | 256 | ARIN |  VG | 8th Aug 2017 |
| 206.71.8.0/24 | 256 | ARIN | US | 3rd Feb 2017 |
| 206.71.9.0/24 | 256 | ARIN | US | 3rd Feb 2017 |
| 206.72.128.0/19 | 8.2k | ARIN | US | 4th Aug 1995 |
| 206.72.208.0/24 | 256 | ARIN | CA | 27th Jun 2012 |
| 206.72.216.0/22 | 1k | ARIN | US | 1st Jul 2025 |
| 206.80.144.0/20 | 4.1k | ARIN | US | 28th Nov 2016 |
| 206.80.224.0/21 | 2k | ARIN | US | 11th Aug 1995 |
| 206.80.232.0/24 | 256 | ARIN | US | 27th Nov 2017 |
| 206.80.234.0/24 | 256 | ARIN | US | 7th Feb 2018 |
| 206.80.236.0/24 | 256 | ARIN | US | 5th Jul 2023 |
| 206.80.237.0/24 | 256 | ARIN | CA | 30th May 2018 |
| 206.80.238.0/24 | 256 | ARIN | US | 9th Jul 2018 |
| 206.80.239.0/24 | 256 | ARIN | CA | 30th Jul 2018 |
| 206.81.104.0/24 | 256 | ARIN | CA | 31st Aug 2018 |
| 206.81.108.0/24 | 256 | ARIN | CA | 29th Sept 2023 |
| 206.81.109.0/24 | 256 | ARIN | US | 20th Nov 2018 |
| 206.81.64.0/21 | 2k | ARIN | US | 20th Apr 2005 |
| 206.81.72.0/22 | 1k | ARIN | US | 20th Apr 2005 |
| 206.81.80.0/22 | 1k | ARIN | US | 12th Feb 2009 |
| 206.82.104.0/22 | 1k | ARIN | US | 10th Oct 2018 |
| 206.82.109.0/24 | 256 | ARIN | US | 29th Jan 2019 |
| 206.82.110.0/23 | 512 | ARIN | CA | 25th Jan 2019 |
| 206.82.160.0/22 | 1k | ARIN | US | 7th Sept 1995 |
| 206.82.164.0/22 | 1k | ARIN | US | 11th Nov 2008 |
| 206.82.168.0/21 | 2k | ARIN | US | 25th Nov 2008 |
| 206.83.10.0/24 | 256 | ARIN | US | 25th Mar 2019 |
| 206.83.12.0/24 | 256 | ARIN | US | 8th May 2019 |
| 206.83.13.0/24 | 256 | ARIN |  AG | 20th May 2019 |
| 206.83.136.0/24 | 256 | ARIN | US | 6th Jan 2020 |
| 206.83.138.0/24 | 256 | ARIN | US | 28th Jan 2020 |
| 206.83.139.0/24 | 256 | ARIN | US | 28th Oct 2025 |
| 206.83.14.0/24 | 256 | ARIN | US | 30th May 2019 |
| 206.83.140.0/24 | 256 | ARIN | US | 2nd Apr 2020 |
| 206.83.141.0/24 | 256 | ARIN | US | 1st May 2020 |