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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 192.188.170.0/24 | 256 | APNIC |  US | 20th Jul 1992 |
| 192.188.172.0/24 | 256 | APNIC |  TH | 23rd Feb 2011 |
| 192.188.173.0/24 | 256 | ARIN | US | 20th Jul 1992 |
| 192.188.174.0/24 | 256 | APNIC |  PH | 20th Jul 1992 |
| 192.188.175.0/24 | 256 | APNIC |  ID | 20th Jul 1992 |
| 192.188.18.0/24 | 256 | ARIN | US | 18th Jun 1992 |
| 192.188.181.0/24 | 256 | ARIN | US | 21st Jul 1992 |
| 192.188.184.0/24 | 256 | ARIN | US | 21st Jul 1992 |
| 192.188.187.0/24 | 256 | RIPE NCC |  RU | 21st Jul 1992 |
| 192.188.188.0/24 | 256 | ARIN | US | 21st Jul 1992 |
| 192.188.19.0/24 | 256 | ARIN | US | 18th Jun 1992 |
| 192.188.190.0/24 | 256 | ARIN | US | 22nd Jul 1992 |
| 192.188.192.0/24 | 256 | ARIN | US | 23rd Jul 1992 |
| 192.188.193.0/24 | 256 | ARIN | US | 24th Jul 1992 |
| 192.188.194.0/24 | 256 | LACNIC |  EC | 24th Jul 1992 |
| 192.188.195.0/24 | 256 | LACNIC | EC | 24th Jul 1992 |
| 192.188.197.0/24 | 256 | LACNIC | EC | 24th Jul 1992 |
| 192.188.198.0/24 | 256 | ARIN | US | 24th Jul 1992 |
| 192.188.20.0/24 | 256 | ARIN | US | 18th Jun 1992 |
| 192.188.200.0/24 | 256 | ARIN | US | 27th Jul 1992 |
| 192.188.204.0/22 | 1k | ARIN | US | 28th Jul 1992 |
| 192.188.21.0/24 | 256 | ARIN | US | 18th Jun 1992 |
| 192.188.228.0/23 | 512 | ARIN | US | 28th Jul 1992 |
| 192.188.236.0/23 | 512 | RIPE NCC |  PL | 30th Jul 1992 |
| 192.188.238.0/23 | 512 | ARIN | US | 30th Jul 1992 |
| 192.188.240.0/24 | 256 | ARIN | US | 30th Jul 1992 |
| 192.188.249.0/24 | 256 | ARIN | US | 30th Jul 1992 |
| 192.188.251.0/24 | 256 | ARIN | US | 16th Jul 2015 |
| 192.188.252.0/24 | 256 | ARIN | US | 31st Jul 1992 |
| 192.188.255.0/24 | 256 | ARIN | US | 23rd Jul 2015 |
| 192.188.44.0/24 | 256 | LACNIC | EC | 19th Jun 1992 |
| 192.188.54.0/24 | 256 | LACNIC | EC | 19th Jun 1992 |
| 192.188.56.0/24 | 256 | LACNIC | EC | 19th Jun 1992 |
| 192.188.60.0/24 | 256 | LACNIC | EC | 22nd Jun 1992 |
| 192.188.62.0/24 | 256 | ARIN | US | 22nd Jun 1992 |
| 192.188.63.0/24 | 256 | RIPE NCC |  GB | 23rd Jun 1992 |
| 192.188.64.0/24 | 256 | RIPE NCC | GB | 23rd Jun 1992 |
| 192.188.65.0/24 | 256 | RIPE NCC |  FR | 24th Jun 1992 |
| 192.188.66.0/24 | 256 | ARIN | US | 24th Jun 1992 |
| 192.188.67.0/24 | 256 | ARIN | US | 24th Jun 1992 |
| 192.188.68.0/24 | 256 | ARIN | US | 24th Jun 1992 |
| 192.188.69.0/24 | 256 | RIPE NCC | GB | 24th Jun 1992 |
| 192.188.70.0/24 | 256 | ARIN | US | 24th Jun 1992 |
| 192.188.75.0/24 | 256 | APNIC |  JP | 23rd Jun 1993 |
| 192.188.76.0/24 | 256 | APNIC | JP | 23rd Jun 1993 |
| 192.188.77.0/24 | 256 | APNIC | JP | 15th Jun 1993 |
| 192.188.78.0/23 | 512 | APNIC | JP | 15th Jun 1993 |
| 192.188.82.0/23 | 512 | APNIC |  HK | 5th Jan 2018 |
| 192.188.92.0/24 | 256 | APNIC | JP | 15th Feb 1994 |
| 192.188.93.0/24 | 256 | ARIN | US | 24th Jun 1992 |