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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 192.160.185.0/24 | 256 | ARIN |  US | 3rd Jun 1992 |
| 192.160.186.0/24 | 256 | ARIN | US | 3rd Jun 1992 |
| 192.160.187.0/24 | 256 | ARIN | US | 3rd Jun 1992 |
| 192.160.189.0/24 | 256 | ARIN | US | 3rd Jun 1992 |
| 192.160.190.0/24 | 256 | ARIN | US | 3rd Jun 1992 |
| 192.160.191.0/24 | 256 | ARIN | US | 3rd Jun 1992 |
| 192.160.195.0/24 | 256 | RIPE NCC |  GB | 8th Jun 1992 |
| 192.160.199.0/24 | 256 | ARIN | US | 9th Jun 1992 |
| 192.160.2.0/24 | 256 | ARIN | US | 21st Apr 1992 |
| 192.160.20.0/24 | 256 | ARIN | US | 22nd Apr 1992 |
| 192.160.200.0/23 | 512 | ARIN | US | 9th Jun 1992 |
| 192.160.202.0/24 | 256 | ARIN | US | 9th Jun 1992 |
| 192.160.203.0/24 | 256 | ARIN | US | 9th Jun 1992 |
| 192.160.21.0/24 | 256 | RIPE NCC |  TR | 22nd Apr 1992 |
| 192.160.214.0/24 | 256 | ARIN | US | 1st Jul 2026 |
| 192.160.225.0/24 | 256 | RIPE NCC |  NO | 1st Sept 1993 |
| 192.160.226.0/24 | 256 | APNIC |  NZ | 21st Jan 2011 |
| 192.160.23.0/24 | 256 | RIPE NCC | NO | 1st Apr 2005 |
| 192.160.230.0/24 | 256 | ARIN | US | 11th Jun 1992 |
| 192.160.231.0/24 | 256 | RIPE NCC |  AT | 11th Jun 1992 |
| 192.160.232.0/24 | 256 | RIPE NCC | AT | 11th Jun 1992 |
| 192.160.234.0/24 | 256 | ARIN | US | 11th Jun 1992 |
| 192.160.235.0/24 | 256 | ARIN | US | 11th Jun 1992 |
| 192.160.236.0/24 | 256 | ARIN | US | 6th Dec 2017 |
| 192.160.238.0/24 | 256 | ARIN | US | 6th Dec 2017 |
| 192.160.239.0/24 | 256 | ARIN | US | 6th Dec 2017 |
| 192.160.24.0/24 | 256 | ARIN | US | 16th Sept 2015 |
| 192.160.240.0/24 | 256 | ARIN | US | 6th Dec 2017 |
| 192.160.241.0/24 | 256 | ARIN | US | 15th Jun 1992 |
| 192.160.25.0/24 | 256 | ARIN | US | 24th Apr 1992 |
| 192.160.252.0/24 | 256 | RIPE NCC |  IL | 29th Oct 1993 |
| 192.160.253.0/24 | 256 | ARIN | US | 15th Jun 1992 |
| 192.160.26.0/24 | 256 | ARIN | US | 24th Apr 1992 |
| 192.160.27.0/24 | 256 | RIPE NCC |  IT | 24th Apr 1992 |
| 192.160.29.0/24 | 256 | APNIC |  TW | 16th Jan 2026 |
| 192.160.30.0/24 | 256 | ARIN | US | 27th Apr 1992 |
| 192.160.31.0/24 | 256 | ARIN | US | 27th Apr 1992 |
| 192.160.32.0/24 | 256 | ARIN | US | 27th Apr 1992 |
| 192.160.33.0/24 | 256 | RIPE NCC |  ES | 27th Apr 1992 |
| 192.160.34.0/24 | 256 | ARIN | US | 2nd Jul 2025 |
| 192.160.35.0/24 | 256 | ARIN | US | 27th Apr 1992 |
| 192.160.36.0/24 | 256 | ARIN | US | 27th Apr 1992 |
| 192.160.37.0/24 | 256 | RIPE NCC | IT | 27th Apr 1992 |
| 192.160.38.0/24 | 256 | ARIN | US | 27th Apr 1992 |
| 192.160.39.0/24 | 256 | ARIN | US | 28th Apr 1992 |
| 192.160.4.0/24 | 256 | ARIN | US | 21st Apr 1992 |
| 192.160.40.0/24 | 256 | ARIN | US | 28th Apr 1992 |
| 192.160.41.0/24 | 256 | ARIN | US | 28th Apr 1992 |
| 192.160.42.0/24 | 256 | ARIN | US | 4th May 1992 |
| 192.160.43.0/24 | 256 | ARIN | US | 4th May 1992 |