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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,149 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.190.104.0/24 | 256 | ARIN |  US | 23rd Jun 1992 |
| 192.190.105.0/24 | 256 | ARIN | US | 23rd Jun 1992 |
| 192.190.108.0/24 | 256 | APNIC |  NZ | 23rd Jun 1992 |
| 192.190.11.0/24 | 256 | ARIN | US | 8th Oct 1992 |
| 192.190.111.0/24 | 256 | ARIN | US | 12th Jul 1994 |
| 192.190.116.0/24 | 256 | ARIN | US | 23rd Jun 1992 |
| 192.190.117.0/24 | 256 | ARIN | US | 23rd Jun 1992 |
| 192.190.118.0/24 | 256 | ARIN | US | 23rd Jun 1992 |
| 192.190.119.0/24 | 256 | ARIN | US | 23rd Jun 1992 |
| 192.190.12.0/24 | 256 | ARIN | US | 18th Sept 1992 |
| 192.190.120.0/24 | 256 | ARIN | US | 23rd Jun 1992 |
| 192.190.128.0/24 | 256 | ARIN | US | 24th Jun 1992 |
| 192.190.13.0/24 | 256 | ARIN | US | 26th Oct 1992 |
| 192.190.131.0/24 | 256 | RIPE NCC |  FR | 24th Jun 1992 |
| 192.190.132.0/24 | 256 | RIPE NCC | FR | 24th Jun 1992 |
| 192.190.14.0/24 | 256 | ARIN | US | 12th Oct 1992 |
| 192.190.148.0/22 | 1k | ARIN | US | 15th Jan 2021 |
| 192.190.15.0/24 | 256 | ARIN | US | 20th Jul 2015 |
| 192.190.17.0/24 | 256 | ARIN | US | 12th Oct 1992 |
| 192.190.175.0/24 | 256 | ARIN | US | 24th Jun 1992 |
| 192.190.176.0/24 | 256 | ARIN | US | 24th Jun 1992 |
| 192.190.178.0/24 | 256 | ARIN | US | 24th Jun 1992 |
| 192.190.179.0/24 | 256 | ARIN | US | 24th Jun 1992 |
| 192.190.18.0/24 | 256 | ARIN | US | 12th Oct 1992 |
| 192.190.181.0/24 | 256 | APNIC |  AU | 7th Aug 2025 |
| 192.190.182.0/24 | 256 | RIPE NCC |  GB | 25th Jun 1992 |
| 192.190.183.0/24 | 256 | RIPE NCC | GB | 25th Jun 1992 |
| 192.190.19.0/24 | 256 | ARIN |  CA | 12th Jul 2019 |
| 192.190.191.0/24 | 256 | RIPE NCC |  NO | 29th Jun 1992 |
| 192.190.193.0/24 | 256 | RIPE NCC | NO | 29th Jun 1992 |
| 192.190.194.0/24 | 256 | ARIN | US | 29th Jun 1992 |
| 192.190.195.0/24 | 256 | ARIN | US | 29th Jun 1992 |
| 192.190.196.0/24 | 256 | ARIN | US | 29th Jun 1992 |
| 192.190.197.0/24 | 256 | ARIN | US | 29th Jun 1992 |
| 192.190.198.0/24 | 256 | ARIN | US | 29th Jun 1992 |
| 192.190.199.0/24 | 256 | ARIN | US | 29th Jun 1992 |
| 192.190.2.0/24 | 256 | ARIN | US | 15th Jun 1992 |
| 192.190.20.0/23 | 512 | ARIN | US | 3rd Apr 2015 |
| 192.190.200.0/24 | 256 | ARIN | US | 29th Jun 1992 |
| 192.190.203.0/24 | 256 | ARIN | US | 29th Jun 1992 |
| 192.190.208.0/24 | 256 | APNIC | AU | 30th Jun 1992 |
| 192.190.210.0/23 | 512 | APNIC | AU | 30th Jun 1992 |
| 192.190.212.0/22 | 1k | APNIC | AU | 30th Jun 1992 |
| 192.190.22.0/24 | 256 | ARIN | US | 29th Oct 1992 |
| 192.190.224.0/24 | 256 | ARIN | US | 1st Jul 1992 |
| 192.190.23.0/24 | 256 | ARIN | US | 15th Jun 1992 |
| 192.190.232.0/24 | 256 | ARIN | US | 21st Jul 2021 |
| 192.190.233.0/24 | 256 | RIPE NCC | FR | 8th Jul 1992 |
| 192.190.234.0/23 | 512 | RIPE NCC | FR | 8th Jul 1992 |
| 192.190.236.0/24 | 256 | RIPE NCC | FR | 8th Jul 1992 |