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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,041 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 167.150.172.0/23 | 512 | ARIN |  US | 2nd Aug 1993 |
| 167.150.176.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.187.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.20.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.201.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.214.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.217.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.218.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.221.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.222.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.226.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.228.0/22 | 1k | ARIN | US | 2nd Aug 1993 |
| 167.150.23.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.232.0/23 | 512 | ARIN | US | 7th Nov 2025 |
| 167.150.234.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.240.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.248.0/21 | 2k | ARIN | US | 2nd Aug 1993 |
| 167.150.28.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.29.0/24 | 256 | ARIN | US | 28th Oct 2025 |
| 167.150.30.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.32.0/19 | 8.2k | ARIN | US | 2nd Aug 1993 |
| 167.150.72.0/21 | 2k | ARIN | US | 2nd Aug 1993 |
| 167.150.8.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.150.80.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.87.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.88.0/24 | 256 | ARIN | US | 2nd Aug 1993 |
| 167.150.92.0/22 | 1k | ARIN | US | 2nd Aug 1993 |
| 167.150.98.0/23 | 512 | ARIN | US | 2nd Aug 1993 |
| 167.151.0.0/16 | 65.5k | ARIN | US | 2nd Aug 1993 |
| 167.152.0.0/16 | 65.5k | ARIN | US | 2nd Aug 1993 |
| 167.156.0.0/16 | 65.5k | ARIN | US | 6th Aug 1993 |
| 167.158.0.0/16 | 65.5k | ARIN | US | 9th Aug 1993 |
| 167.160.21.0/24 | 256 | RIPE NCC |  GE | 3rd Mar 2014 |
| 167.160.24.0/23 | 512 | RIPE NCC |  ES | 3rd Mar 2014 |
| 167.160.30.0/24 | 256 | RIPE NCC | GE | 3rd Mar 2014 |
| 167.163.0.0/16 | 65.5k | ARIN | US | 11th Aug 1993 |
| 167.168.0.0/16 | 65.5k | RIPE NCC |  CH | 1st Sept 1993 |
| 167.17.88.0/21 | 2k | ARIN | US | 8th Aug 2025 |
| 167.178.0.0/16 | 65.5k | ARIN | US | 17th Jul 2018 |
| 167.179.212.0/22 | 1k | APNIC |  KR | 8th Sept 1993 |
| 167.180.0.0/16 | 65.5k | ARIN | US | 9th Sept 1993 |
| 167.182.128.0/17 | 32.8k | ARIN | US | 10th Sept 1993 |
| 167.185.0.0/16 | 65.5k | ARIN | US | 13th Sept 1993 |
| 167.189.0.0/16 | 65.5k | APNIC |  CN | 16th Sept 1993 |
| 167.190.0.0/16 | 65.5k | ARIN | US | 21st Sept 1993 |
| 167.202.0.0/17 | 32.8k | ARIN | US | 27th Sept 1993 |
| 167.202.128.0/18 | 16.4k | ARIN | US | 27th Sept 1993 |
| 167.202.224.0/19 | 8.2k | ARIN | US | 27th Sept 1993 |
| 167.213.0.0/16 | 65.5k | ARIN | US | 12th Oct 1993 |
| 167.214.0.0/16 | 65.5k | ARIN | US | 12th Oct 1993 |