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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 unannounced space registered through ARIN, largest first.
Unannounced blocks registered through ARIN
30,434 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 162.54.128.0/17 | 32.8k | ARIN |  US | 3rd Aug 1992 |
| 162.63.0.0/16 | 65.5k | ARIN | US | 12th Aug 1992 |
| 162.64.0.0/16 | 65.5k | ARIN | US | 12th Aug 1992 |
| 162.66.0.0/16 | 65.5k | ARIN | US | 12th Aug 1992 |
| 162.7.0.0/16 | 65.5k | ARIN | US | 17th Jun 1992 |
| 162.76.0.0/16 | 65.5k | ARIN | US | 24th Aug 1992 |
| 162.77.0.0/16 | 65.5k | ARIN | US | 24th Aug 1992 |
| 162.89.16.0/22 | 1k | ARIN | US | 17th Sept 1992 |
| 162.89.24.0/21 | 2k | ARIN | US | 17th Sept 1992 |
| 162.89.32.0/19 | 8.2k | ARIN | US | 17th Sept 1992 |
| 162.91.0.0/16 | 65.5k | ARIN | US | 17th Sept 1992 |
| 163.123.176.0/24 | 256 | ARIN | US | 12th Oct 2020 |
| 163.123.177.0/24 | 256 | ARIN | US | 29th Sept 2020 |
| 163.123.188.0/24 | 256 | ARIN | US | 8th Oct 2020 |
| 163.123.190.0/24 | 256 | ARIN | US | 19th Nov 2020 |
| 163.123.196.0/24 | 256 | ARIN | US | 30th Sept 2020 |
| 163.123.217.0/24 | 256 | ARIN |  CA | 30th Sept 2020 |
| 163.123.224.0/24 | 256 | ARIN | US | 30th Sept 2020 |
| 163.123.225.0/24 | 256 | ARIN | US | 29th Sept 2020 |
| 163.123.248.0/22 | 1k | ARIN | US | 29th Sept 2020 |
| 163.154.0.0/16 | 65.5k | ARIN | US | 18th Jul 2018 |
| 163.165.0.0/17 | 32.8k | ARIN | US | 20th Feb 2024 |
| 163.182.164.0/24 | 256 | ARIN | CA | 8th Jan 2020 |
| 163.190.0.0/16 | 65.5k | ARIN | US | 13th Aug 1992 |
| 163.231.0.0/16 | 65.5k | ARIN | US | 25th Aug 1992 |
| 163.241.0.0/16 | 65.5k | ARIN | US | 17th Sept 1992 |
| 163.243.0.0/16 | 65.5k | ARIN | US | 25th Sept 1992 |
| 163.245.32.0/19 | 8.2k | ARIN | US | 28th Sept 1992 |
| 163.245.64.0/18 | 16.4k | ARIN | US | 28th Sept 1992 |
| 163.254.0.0/16 | 65.5k | ARIN | US | 23rd Oct 1992 |
| 163.33.0.0/16 | 65.5k | ARIN | US | 6th Jul 1992 |
| 163.35.0.0/16 | 65.5k | ARIN | US | 6th Jul 1992 |
| 163.36.0.0/14 | 262k | ARIN | US | 6th Jul 1992 |
| 163.47.183.0/24 | 256 | ARIN | US | 17th Mar 2020 |
| 164.101.0.0/16 | 65.5k | ARIN | US | 4th Feb 1993 |
| 164.103.0.0/16 | 65.5k | ARIN | US | 8th Feb 1993 |
| 164.109.0.0/16 | 65.5k | ARIN | US | 18th Feb 1993 |
| 164.118.0.0/16 | 65.5k | ARIN | US | 19th Mar 1993 |
| 164.120.0.0/16 | 65.5k | ARIN | US | 8th Mar 1993 |
| 164.123.0.0/16 | 65.5k | ARIN | US | 9th Mar 1993 |
| 164.144.0.0/16 | 65.5k | ARIN | US | 9th Mar 1993 |
| 164.152.0.0/22 | 1k | ARIN | US | 12th Mar 1993 |
| 164.152.120.0/23 | 512 | ARIN | US | 12th Mar 1993 |
| 164.152.126.0/23 | 512 | ARIN | US | 12th Mar 1993 |
| 164.152.128.0/22 | 1k | ARIN | US | 12th Mar 1993 |
| 164.152.144.0/21 | 2k | ARIN | US | 12th Mar 1993 |
| 164.152.152.0/22 | 1k | ARIN | US | 12th Mar 1993 |
| 164.152.156.0/24 | 256 | ARIN | US | 12th Mar 1993 |
| 164.152.164.0/24 | 256 | ARIN | US | 12th Mar 1993 |
| 164.152.176.0/24 | 256 | ARIN | US | 12th Mar 1993 |