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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,124 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.158.61.0/24 | 256 | ARIN |  US | 4th May 1992 |
| 192.158.64.0/19 | 8.2k | ARIN | US | 21st Apr 1992 |
| 192.158.96.0/21 | 2k | ARIN |  CA | 17th Aug 2026 |
| 192.159.105.0/24 | 256 | RIPE NCC |  NL | 6th May 1992 |
| 192.159.107.0/24 | 256 | ARIN | US | 6th May 1992 |
| 192.159.108.0/24 | 256 | RIPE NCC |  NO | 6th May 1992 |
| 192.159.109.0/24 | 256 | RIPE NCC |  IE | 6th May 1992 |
| 192.159.11.0/24 | 256 | ARIN | US | 8th Jan 1993 |
| 192.159.112.0/24 | 256 | ARIN | US | 6th May 1992 |
| 192.159.113.0/24 | 256 | ARIN | US | 6th May 1992 |
| 192.159.114.0/24 | 256 | ARIN | US | 6th May 1992 |
| 192.159.115.0/24 | 256 | ARIN | US | 6th May 1992 |
| 192.159.118.0/24 | 256 | RIPE NCC | IE | 7th May 1992 |
| 192.159.12.0/24 | 256 | ARIN | US | 20th Apr 1992 |
| 192.159.122.0/24 | 256 | RIPE NCC |  FI | 7th May 1992 |
| 192.159.128.0/24 | 256 | ARIN | US | 5th May 1992 |
| 192.159.129.0/24 | 256 | ARIN | US | 5th May 1992 |
| 192.159.13.0/24 | 256 | ARIN | US | 8th Jan 1993 |
| 192.159.130.0/24 | 256 | ARIN | US | 5th May 1992 |
| 192.159.135.0/24 | 256 | ARIN | US | 5th May 1992 |
| 192.159.136.0/24 | 256 | ARIN | US | 5th May 1992 |
| 192.159.137.0/24 | 256 | ARIN | US | 5th May 1992 |
| 192.159.139.0/24 | 256 | ARIN | US | 5th May 1992 |
| 192.159.14.0/24 | 256 | ARIN | US | 20th Apr 1992 |
| 192.159.140.0/24 | 256 | ARIN | US | 5th May 1992 |
| 192.159.141.0/24 | 256 | ARIN | US | 5th May 1992 |
| 192.159.15.0/24 | 256 | ARIN | US | 23rd Oct 1992 |
| 192.159.16.0/21 | 2k | APNIC | NL | 20th Apr 1992 |
| 192.159.2.0/24 | 256 | ARIN | US | 12th Nov 1993 |
| 192.159.224.0/19 | 8.2k | ARIN | CA | 30th Jan 2013 |
| 192.159.24.0/24 | 256 | APNIC |  SG | 20th Apr 1992 |
| 192.159.25.0/24 | 256 | APNIC | SG | 20th Apr 1992 |
| 192.159.26.0/24 | 256 | APNIC | SG | 20th Apr 1992 |
| 192.159.27.0/24 | 256 | APNIC | SG | 20th Apr 1992 |
| 192.159.28.0/24 | 256 | APNIC | SG | 20th Apr 1992 |
| 192.159.29.0/24 | 256 | APNIC | SG | 20th Apr 1992 |
| 192.159.3.0/24 | 256 | ARIN | US | 20th Apr 1992 |
| 192.159.30.0/24 | 256 | APNIC | SG | 20th Apr 1992 |
| 192.159.4.0/24 | 256 | ARIN | US | 8th Jan 1993 |
| 192.159.5.0/24 | 256 | ARIN | US | 20th Apr 1992 |
| 192.159.6.0/24 | 256 | ARIN | US | 8th Jan 1993 |
| 192.159.7.0/24 | 256 | ARIN | US | 21st Oct 1993 |
| 192.159.70.0/24 | 256 | RIPE NCC | FI | 28th Apr 1992 |
| 192.159.71.0/24 | 256 | ARIN | CA | 28th Apr 1992 |
| 192.159.72.0/24 | 256 | ARIN | US | 28th Apr 1992 |
| 192.159.73.0/24 | 256 | RIPE NCC |  GB | 28th Apr 1992 |
| 192.159.74.0/24 | 256 | ARIN | US | 29th Apr 1992 |
| 192.159.75.0/24 | 256 | ARIN | US | 29th Apr 1992 |
| 192.159.76.0/24 | 256 | ARIN | US | 29th Apr 1992 |
| 192.159.77.0/24 | 256 | RIPE NCC |  IT | 29th Apr 1992 |