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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 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 |
| 168.113.128.0/19 | 8.2k | RIPE NCC |  SC | 24th Mar 1994 |
| 168.113.160.0/20 | 4.1k | RIPE NCC | SC | 24th Mar 1994 |
| 168.113.176.0/20 | 4.1k | RIPE NCC |  RU | 24th Mar 1994 |
| 168.113.192.0/20 | 4.1k | RIPE NCC | RU | 24th Mar 1994 |
| 168.113.208.0/22 | 1k | RIPE NCC | RU | 24th Mar 1994 |
| 168.113.212.0/22 | 1k | RIPE NCC | RU | 24th Mar 1994 |
| 168.113.216.0/21 | 2k | RIPE NCC |  KG | 24th Mar 1994 |
| 168.113.224.0/22 | 1k | RIPE NCC |  CA | 24th Mar 1994 |
| 168.113.228.0/23 | 512 | RIPE NCC | KG | 24th Mar 1994 |
| 168.113.230.0/24 | 256 | RIPE NCC | KG | 24th Mar 1994 |
| 168.113.231.0/24 | 256 | RIPE NCC | CA | 24th Mar 1994 |
| 168.113.232.0/21 | 2k | RIPE NCC | RU | 24th Mar 1994 |
| 168.113.244.0/22 | 1k | RIPE NCC | RU | 24th Mar 1994 |
| 168.113.248.0/23 | 512 | RIPE NCC | RU | 24th Mar 1994 |
| 168.113.250.0/24 | 256 | RIPE NCC | RU | 24th Mar 1994 |
| 168.113.251.0/24 | 256 | RIPE NCC | RU | 24th Mar 1994 |
| 168.113.252.0/22 | 1k | RIPE NCC | RU | 24th 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 |
| 168.121.128.0/22 | 1k | LACNIC |  PA | 1st Feb 2016 |
| 168.121.164.0/22 | 1k | LACNIC |  BR | 5th Feb 2016 |
| 168.121.244.0/22 | 1k | LACNIC | BR | 5th Mar 2021 |
| 168.125.0.0/16 | 65.5k | ARIN | US | 19th Apr 1994 |
| 168.128.0.0/16 | 65.5k | AFRINIC |  ZA | 21st Apr 1994 |
| 168.130.0.0/16 | 65.5k | APNIC |  AU | 25th Apr 1994 |
| 168.136.0.0/16 | 65.5k | ARIN | US | 9th May 1994 |
| 168.139.0.0/16 | 65.5k | RIPE NCC |  TR | 10th May 1994 |
| 168.140.0.0/17 | 32.8k | ARIN | US | 16th May 2022 |
| 168.140.192.0/22 | 1k | APNIC | AU | 10th May 1994 |
| 168.140.200.0/21 | 2k | APNIC | AU | 10th May 1994 |
| 168.140.208.0/20 | 4.1k | APNIC | AU | 10th May 1994 |
| 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 |
| 168.151.17.0/24 | 256 | ARIN | CA | 16th Jan 2019 |
| 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 |