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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,201 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.41.141.0/24 | 256 | RIPE NCC |  CH | 30th Jun 1988 |
| 192.41.142.0/23 | 512 | RIPE NCC | CH | 30th Jun 1988 |
| 192.41.144.0/23 | 512 | RIPE NCC | CH | 30th Jun 1988 |
| 192.41.147.0/24 | 256 | RIPE NCC |  DE | 14th Dec 1993 |
| 192.41.161.0/24 | 256 | ARIN |  US | 7th Jul 1988 |
| 192.41.163.0/24 | 256 | ARIN | US | 7th Jul 1988 |
| 192.41.173.0/24 | 256 | ARIN | US | 13th Jun 1988 |
| 192.41.174.0/24 | 256 | ARIN | US | 13th Jun 1988 |
| 192.41.175.0/24 | 256 | ARIN | US | 13th Jun 1988 |
| 192.41.176.0/24 | 256 | ARIN | US | 13th Jun 1988 |
| 192.41.178.0/23 | 512 | APNIC |  JP | 20th Jun 1988 |
| 192.41.180.0/22 | 1k | APNIC | JP | 20th Jun 1988 |
| 192.41.184.0/21 | 2k | APNIC | JP | 20th Jun 1988 |
| 192.41.193.0/24 | 256 | APNIC | JP | 20th Jun 1988 |
| 192.41.194.0/23 | 512 | APNIC | JP | 20th Jun 1988 |
| 192.41.196.0/23 | 512 | APNIC | JP | 20th Jun 1988 |
| 192.41.198.0/24 | 256 | ARIN | US | 20th Jun 1988 |
| 192.41.199.0/24 | 256 | ARIN | US | 21st Jun 1988 |
| 192.41.201.0/24 | 256 | ARIN |  CA | 22nd Jun 1988 |
| 192.41.205.0/24 | 256 | ARIN | US | 23rd Jun 1988 |
| 192.41.206.0/24 | 256 | APNIC |  ID | 24th Jun 1988 |
| 192.41.210.0/24 | 256 | RIPE NCC |  GB | 27th Jun 1988 |
| 192.41.212.0/24 | 256 | ARIN | US | 13th Sept 1988 |
| 192.41.213.0/24 | 256 | ARIN | US | 4th May 1993 |
| 192.41.215.0/24 | 256 | ARIN | US | 13th Jul 1988 |
| 192.41.217.0/24 | 256 | ARIN | US | 14th Jul 1988 |
| 192.41.219.0/24 | 256 | ARIN | US | 18th Jul 1988 |
| 192.41.224.0/24 | 256 | ARIN | US | 21st Jul 1988 |
| 192.41.225.0/24 | 256 | ARIN | US | 22nd Jul 1988 |
| 192.41.238.0/24 | 256 | ARIN | US | 26th Jul 1988 |
| 192.41.239.0/24 | 256 | ARIN | US | 26th Jul 1988 |
| 192.41.240.0/22 | 1k | ARIN | US | 26th Jul 1988 |
| 192.41.244.0/24 | 256 | ARIN | US | 26th Jul 1988 |
| 192.41.247.0/24 | 256 | ARIN | US | 11th Nov 1988 |
| 192.42.1.0/24 | 256 | RIPE NCC | DE | 14th Nov 1988 |
| 192.42.10.0/23 | 512 | ARIN | US | 8th Aug 1988 |
| 192.42.102.0/24 | 256 | RIPE NCC |  FR | 13th Apr 1992 |
| 192.42.103.0/24 | 256 | APNIC | JP | 21st Sept 1988 |
| 192.42.104.0/22 | 1k | APNIC | JP | 21st Sept 1988 |
| 192.42.108.0/24 | 256 | ARIN | US | 21st Sept 1988 |
| 192.42.109.0/24 | 256 | ARIN | US | 22nd Sept 1988 |
| 192.42.111.0/24 | 256 | ARIN | US | 29th Jun 1993 |
| 192.42.112.0/24 | 256 | ARIN | US | 18th Jul 2014 |
| 192.42.12.0/22 | 1k | ARIN | US | 8th Aug 1988 |
| 192.42.133.0/24 | 256 | ARIN | US | 27th Sept 1988 |
| 192.42.134.0/23 | 512 | ARIN | US | 27th Sept 1988 |
| 192.42.136.0/24 | 256 | ARIN | US | 27th Sept 1988 |
| 192.42.137.0/24 | 256 | ARIN | US | 4th Oct 1988 |
| 192.42.138.0/24 | 256 | ARIN | US | 4th Oct 1988 |
| 192.42.139.0/24 | 256 | ARIN | US | 4th Oct 1988 |