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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
84,960 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 104.247.0.0/19 | 8.2k | ARIN |  US | 24th Dec 2014 |
| 104.247.124.0/24 | 256 | ARIN | US | 8th Jul 2021 |
| 104.247.125.0/24 | 256 | ARIN | US | 19th Jul 2021 |
| 104.247.93.0/24 | 256 | ARIN | US | 29th Jun 2016 |
| 104.247.94.0/23 | 512 | ARIN | US | 29th Jun 2016 |
| 104.247.96.0/24 | 256 | ARIN |  CA | 6th Jul 2026 |
| 104.247.99.0/24 | 256 | ARIN | US | 13th Jan 2026 |
| 104.249.134.0/24 | 256 | ARIN | US | 7th Apr 2021 |
| 104.249.135.0/24 | 256 | ARIN | US | 26th Apr 2021 |
| 104.249.169.0/24 | 256 | ARIN | US | 12th Apr 2021 |
| 104.250.228.0/24 | 256 | ARIN | US | 2nd Jul 2021 |
| 104.250.231.0/24 | 256 | ARIN | US | 1st Jul 2021 |
| 104.250.240.0/22 | 1k | ARIN | US | 1st Jul 2021 |
| 104.251.192.0/20 | 4.1k | ARIN | US | 29th Dec 2014 |
| 104.254.112.0/21 | 2k | ARIN | US | 2nd Jan 2015 |
| 104.254.132.0/22 | 1k | ARIN | US | 23rd Jan 2015 |
| 104.254.24.0/21 | 2k | ARIN | US | 23rd Dec 2014 |
| 104.254.96.0/23 | 512 | ARIN |  VG | 31st Dec 2014 |
| 104.255.120.0/22 | 1k | ARIN | US | 28th Jan 2015 |
| 104.255.136.0/22 | 1k | ARIN | US | 28th Sept 2016 |
| 104.255.216.0/22 | 1k | ARIN | US | 4th Feb 2015 |
| 104.255.34.0/24 | 256 | ARIN | US | 22nd Aug 2018 |
| 104.36.144.0/22 | 1k | ARIN | US | 3rd Jun 2014 |
| 104.36.204.0/22 | 1k | ARIN | US | 6th Jun 2014 |
| 104.36.51.0/24 | 256 | ARIN | US | 28th Mar 2025 |
| 104.37.116.0/22 | 1k | ARIN | US | 23rd Jun 2014 |
| 104.37.168.0/22 | 1k | ARIN | US | 18th Jun 2014 |
| 104.37.240.0/22 | 1k | ARIN | CA | 7th Jul 2014 |
| 104.37.48.0/22 | 1k | ARIN | US | 25th Apr 2024 |
| 104.37.8.0/21 | 2k | ARIN | US | 9th Apr 2025 |
| 105.238.0.0/15 | 131k | AFRINIC |  SD | 28th Jun 2012 |
| 105.48.0.0/12 | 1M | AFRINIC |  KE | 30th Jan 2014 |
| 106.0.0.0/24 | 256 | APNIC |  CN | 14th Apr 2011 |
| 106.0.1.0/24 | 256 | APNIC |  AU | 2nd Mar 2011 |
| 106.0.16.0/20 | 4.1k | APNIC | CN | 12th Apr 2011 |
| 106.0.2.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 106.0.32.0/22 | 1k | APNIC |  IN | 14th Jan 2016 |
| 106.0.44.0/22 | 1k | APNIC | CN | 14th Jan 2016 |
| 106.0.64.0/18 | 16.4k | APNIC | CN | 12th Apr 2011 |
| 106.0.8.0/21 | 2k | APNIC | CN | 12th Apr 2011 |
| 106.50.0.0/16 | 65.5k | APNIC | CN | 31st Mar 2011 |
| 107.150.136.0/23 | 512 | ARIN | US | 13th Dec 2013 |
| 107.150.162.0/23 | 512 | RIPE NCC |  GE | 17th Dec 2013 |
| 107.150.170.0/24 | 256 | RIPE NCC |  NL | 17th Dec 2013 |
| 107.150.171.0/24 | 256 | RIPE NCC | GE | 17th Dec 2013 |
| 107.150.177.0/24 | 256 | RIPE NCC | GE | 17th Dec 2013 |
| 107.152.16.0/20 | 4.1k | ARIN | US | 27th Nov 2013 |
| 107.155.160.0/20 | 4.1k | ARIN | US | 13th Oct 2022 |
| 107.161.152.0/24 | 256 | ARIN | CA | 17th Sept 2018 |
| 107.161.153.0/24 | 256 | ARIN | US | 23rd Sept 2020 |