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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 in United States
26,993 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 167.94.25.0/24 | 256 | ARIN |  US | 21st May 1993 |
| 167.94.254.0/23 | 512 | ARIN | US | 21st May 1993 |
| 167.94.26.0/23 | 512 | ARIN | US | 21st May 1993 |
| 167.94.28.0/22 | 1k | ARIN | US | 21st May 1993 |
| 167.94.32.0/23 | 512 | ARIN | US | 21st May 1993 |
| 167.94.35.0/24 | 256 | ARIN | US | 21st May 1993 |
| 167.94.36.0/24 | 256 | ARIN | US | 20th Mar 2024 |
| 167.94.37.0/24 | 256 | ARIN | US | 21st May 1993 |
| 167.94.40.0/24 | 256 | ARIN | US | 21st May 1993 |
| 167.94.46.0/24 | 256 | ARIN | US | 21st May 1993 |
| 167.94.48.0/23 | 512 | ARIN | US | 21st May 1993 |
| 167.94.51.0/24 | 256 | ARIN | US | 21st May 1993 |
| 167.94.52.0/23 | 512 | ARIN | US | 3rd Nov 2021 |
| 167.94.55.0/24 | 256 | ARIN | US | 21st May 1993 |
| 167.94.56.0/22 | 1k | ARIN | US | 21st May 1993 |
| 167.94.6.0/24 | 256 | ARIN | US | 21st May 1993 |
| 167.94.60.0/23 | 512 | ARIN | US | 21st May 1993 |
| 167.94.64.0/24 | 256 | ARIN | US | 12th May 2022 |
| 167.94.65.0/24 | 256 | ARIN | US | 21st May 1993 |
| 167.94.78.0/24 | 256 | ARIN | US | 28th Jun 2022 |
| 167.94.79.0/24 | 256 | ARIN | US | 21st May 1993 |
| 167.94.8.0/23 | 512 | ARIN | US | 21st May 1993 |
| 167.94.80.0/24 | 256 | ARIN | US | 21st May 1993 |
| 167.94.88.0/23 | 512 | ARIN | US | 21st May 1993 |
| 167.94.96.0/23 | 512 | ARIN | US | 21st May 1993 |
| 167.94.98.0/24 | 256 | ARIN | US | 21st May 1993 |
| 168.100.20.0/22 | 1k | ARIN | US | 25th Jun 2020 |
| 168.104.0.0/16 | 65.5k | ARIN | US | 15th Mar 1994 |
| 168.108.0.0/16 | 65.5k | ARIN | US | 17th Mar 1994 |
| 168.109.0.0/16 | 65.5k | ARIN | US | 17th Mar 1994 |
| 168.117.0.0/16 | 65.5k | ARIN | US | 29th Mar 1994 |
| 168.118.0.0/16 | 65.5k | ARIN | US | 29th Mar 1994 |
| 168.125.0.0/16 | 65.5k | ARIN | US | 19th Apr 1994 |
| 168.136.0.0/16 | 65.5k | ARIN | US | 9th May 1994 |
| 168.140.0.0/17 | 32.8k | ARIN | US | 16th May 2022 |
| 168.147.0.0/16 | 65.5k | ARIN | US | 29th Mar 1994 |
| 168.151.128.0/20 | 4.1k | ARIN | US | 4th Apr 1994 |
| 168.151.144.0/24 | 256 | ARIN | US | 30th Sept 2025 |
| 168.151.145.0/24 | 256 | ARIN | US | 27th Mar 2026 |
| 168.151.146.0/23 | 512 | ARIN | US | 4th Apr 1994 |
| 168.151.148.0/22 | 1k | ARIN | US | 4th Apr 1994 |
| 168.151.152.0/22 | 1k | ARIN | US | 4th Apr 1994 |
| 168.151.156.0/24 | 256 | ARIN | US | 6th Oct 2025 |
| 168.151.158.0/23 | 512 | ARIN | US | 4th Apr 1994 |
| 168.151.176.0/21 | 2k | ARIN | US | 4th Apr 1994 |
| 168.151.184.0/22 | 1k | ARIN | US | 4th Apr 1994 |
| 168.151.192.0/20 | 4.1k | ARIN | US | 4th Apr 1994 |
| 168.151.208.0/21 | 2k | ARIN | US | 4th Apr 1994 |
| 168.151.21.0/24 | 256 | RIPE NCC | US | 4th Apr 1994 |
| 168.151.216.0/22 | 1k | ARIN | US | 4th Apr 1994 |