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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 192.152.242.0/24 | 256 | ARIN |  US | 12th Jun 1992 |
| 192.152.244.0/24 | 256 | RIPE NCC |  GB | 12th Jun 1992 |
| 192.152.245.0/24 | 256 | ARIN | US | 12th Jun 1992 |
| 192.152.246.0/24 | 256 | ARIN | US | 12th Jun 1992 |
| 192.152.247.0/24 | 256 | ARIN | US | 12th Jun 1992 |
| 192.152.249.0/24 | 256 | ARIN | US | 12th Jun 1992 |
| 192.152.250.0/24 | 256 | ARIN | US | 12th Jun 1992 |
| 192.152.251.0/24 | 256 | ARIN | US | 12th Jun 1992 |
| 192.152.252.0/24 | 256 | ARIN | US | 12th Jun 1992 |
| 192.152.253.0/24 | 256 | RIPE NCC | GB | 12th Jun 1992 |
| 192.152.254.0/24 | 256 | RIPE NCC |  AT | 12th Jun 1992 |
| 192.152.26.0/24 | 256 | RIPE NCC |  DE | 1st Sept 1993 |
| 192.152.27.0/24 | 256 | RIPE NCC | DE | 1st Sept 1993 |
| 192.152.30.0/23 | 512 | ARIN | US | 1st Apr 1992 |
| 192.152.32.0/21 | 2k | ARIN | US | 1st Apr 1992 |
| 192.152.4.0/24 | 256 | ARIN | US | 30th Mar 1992 |
| 192.152.40.0/23 | 512 | ARIN | US | 1st Apr 1992 |
| 192.152.42.0/24 | 256 | RIPE NCC |  FR | 3rd Apr 1992 |
| 192.152.44.0/24 | 256 | RIPE NCC | GB | 3rd Apr 1992 |
| 192.152.47.0/24 | 256 | RIPE NCC |  PT | 30th Jan 1993 |
| 192.152.48.0/24 | 256 | RIPE NCC | GB | 3rd Apr 1992 |
| 192.152.49.0/24 | 256 | RIPE NCC |  NL | 1st Sept 1993 |
| 192.152.50.0/24 | 256 | RIPE NCC | NL | 1st Sept 1993 |
| 192.152.51.0/24 | 256 | RIPE NCC | NL | 1st Sept 1993 |
| 192.152.52.0/24 | 256 | ARIN | US | 6th Apr 1992 |
| 192.152.53.0/24 | 256 | ARIN | US | 6th Apr 1992 |
| 192.152.55.0/24 | 256 | ARIN | US | 7th Apr 1992 |
| 192.152.56.0/24 | 256 | ARIN | US | 7th Apr 1992 |
| 192.152.57.0/24 | 256 | ARIN | US | 7th Apr 1992 |
| 192.152.59.0/24 | 256 | ARIN | US | 8th Apr 1992 |
| 192.152.6.0/24 | 256 | RIPE NCC |  NO | 30th Mar 1992 |
| 192.152.60.0/24 | 256 | ARIN | US | 8th Apr 1992 |
| 192.152.61.0/24 | 256 | RIPE NCC | GB | 8th Apr 1992 |
| 192.152.62.0/24 | 256 | RIPE NCC | GB | 8th Apr 1992 |
| 192.152.63.0/24 | 256 | RIPE NCC | AT | 8th Apr 1992 |
| 192.152.64.0/24 | 256 | ARIN | US | 8th Apr 1992 |
| 192.152.65.0/24 | 256 | ARIN | US | 8th Apr 1992 |
| 192.152.67.0/24 | 256 | ARIN | US | 8th Apr 1992 |
| 192.152.68.0/24 | 256 | RIPE NCC |  FI | 8th Apr 1992 |
| 192.152.69.0/24 | 256 | APNIC |  JP | 8th Apr 1992 |
| 192.152.70.0/24 | 256 | ARIN | US | 8th Apr 1992 |
| 192.152.71.0/24 | 256 | ARIN | US | 9th Apr 1992 |
| 192.152.72.0/24 | 256 | ARIN | US | 9th Apr 1992 |
| 192.152.73.0/24 | 256 | ARIN | US | 9th Apr 1992 |
| 192.152.74.0/24 | 256 | ARIN | US | 9th Apr 1992 |
| 192.152.75.0/24 | 256 | ARIN | US | 9th Apr 1992 |
| 192.152.76.0/24 | 256 | ARIN | US | 9th Apr 1992 |
| 192.152.77.0/24 | 256 | ARIN | US | 9th Apr 1992 |
| 192.152.78.0/24 | 256 | ARIN | US | 9th Apr 1992 |
| 192.152.8.0/24 | 256 | ARIN | US | 30th Mar 1992 |