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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,195 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.5.244.0/22 | 1k | ARIN |  US | 29th Jul 1986 |
| 192.5.254.0/24 | 256 | RIPE NCC |  GB | 30th Jul 1986 |
| 192.5.26.0/24 | 256 | ARIN | US | 19th Apr 1990 |
| 192.5.33.0/24 | 256 | ARIN | US | 3rd Jul 1983 |
| 192.5.34.0/24 | 256 | ARIN | US | 3rd Jul 1983 |
| 192.5.35.0/24 | 256 | ARIN | US | 19th Apr 1990 |
| 192.5.37.0/24 | 256 | ARIN | US | 23rd Apr 1990 |
| 192.5.39.0/24 | 256 | ARIN | US | 1st Nov 1989 |
| 192.5.45.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.5.52.0/24 | 256 | ARIN | US | 13th Feb 1984 |
| 192.5.54.0/24 | 256 | ARIN | US | 27th Feb 1984 |
| 192.5.55.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.5.56.0/24 | 256 | ARIN | US | 30th May 1984 |
| 192.5.57.0/24 | 256 | ARIN | US | 12th Feb 2014 |
| 192.5.61.0/24 | 256 | RIPE NCC |  FR | 3rd Apr 1984 |
| 192.5.62.0/24 | 256 | RIPE NCC | FR | 3rd Apr 1984 |
| 192.5.64.0/24 | 256 | ARIN | US | 13th Apr 1984 |
| 192.5.68.0/23 | 512 | ARIN | US | 17th Jun 2021 |
| 192.5.70.0/24 | 256 | ARIN | US | 1st Jun 1984 |
| 192.5.72.0/24 | 256 | ARIN | US | 1st Nov 1989 |
| 192.5.74.0/23 | 512 | ARIN | US | 20th May 1988 |
| 192.5.76.0/22 | 1k | ARIN | US | 20th May 1988 |
| 192.5.80.0/23 | 512 | ARIN | US | 20th May 1988 |
| 192.5.82.0/24 | 256 | ARIN | US | 25th May 1988 |
| 192.5.83.0/24 | 256 | ARIN | US | 23rd May 1988 |
| 192.5.88.0/24 | 256 | ARIN | US | 25th Feb 1991 |
| 192.5.9.0/24 | 256 | ARIN | US | 19th Jan 1983 |
| 192.5.94.0/24 | 256 | ARIN | US | 10th Jul 1984 |
| 192.5.95.0/24 | 256 | ARIN | US | 10th Jul 1984 |
| 192.5.96.0/24 | 256 | ARIN |  CA | 19th Jul 1984 |
| 192.51.128.0/24 | 256 | APNIC |  JP | 4th Aug 1993 |
| 192.51.129.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.130.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.131.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.132.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.133.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.134.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.135.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.136.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.137.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.138.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.139.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.140.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.141.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.142.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.143.0/24 | 256 | APNIC | JP | 4th Aug 1993 |
| 192.51.152.0/22 | 1k | APNIC | JP | 19th Apr 1994 |
| 192.51.156.0/23 | 512 | APNIC | JP | 4th Aug 1993 |
| 192.51.158.0/24 | 256 | APNIC | JP | 5th Aug 1993 |
| 192.51.159.0/24 | 256 | APNIC | JP | 5th Aug 1993 |