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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 192.108.2.0/24 | 256 | ARIN |  US | 26th Apr 1991 |
| 192.108.20.0/24 | 256 | ARIN | US | 3rd Oct 1994 |
| 192.108.21.0/24 | 256 | ARIN | US | 29th Apr 1991 |
| 192.108.215.0/24 | 256 | ARIN | US | 31st Jul 1991 |
| 192.108.216.0/24 | 256 | ARIN | US | 1st Aug 1991 |
| 192.108.217.0/24 | 256 | ARIN | US | 1st Aug 1991 |
| 192.108.218.0/24 | 256 | ARIN | US | 1st Aug 1991 |
| 192.108.219.0/24 | 256 | ARIN | US | 1st Aug 1991 |
| 192.108.22.0/24 | 256 | ARIN | US | 1st May 1991 |
| 192.108.220.0/24 | 256 | ARIN | US | 1st Aug 1991 |
| 192.108.222.0/24 | 256 | ARIN | US | 21st Sept 1992 |
| 192.108.223.0/24 | 256 | ARIN | US | 30th Jul 1993 |
| 192.108.226.0/24 | 256 | ARIN | US | 1st Aug 1991 |
| 192.108.228.0/24 | 256 | ARIN | US | 2nd Aug 1991 |
| 192.108.229.0/24 | 256 | ARIN | US | 2nd Aug 1991 |
| 192.108.230.0/24 | 256 | APNIC |  TH | 2nd Aug 1991 |
| 192.108.233.0/24 | 256 | ARIN | US | 2nd Aug 1991 |
| 192.108.234.0/24 | 256 | RIPE NCC |  CH | 2nd Aug 1991 |
| 192.108.236.0/24 | 256 | ARIN | US | 5th Aug 1991 |
| 192.108.237.0/24 | 256 | ARIN | US | 5th Aug 1991 |
| 192.108.238.0/24 | 256 | RIPE NCC |  AT | 5th Aug 1991 |
| 192.108.239.0/24 | 256 | ARIN | US | 18th Sept 2015 |
| 192.108.240.0/23 | 512 | ARIN | US | 5th Aug 1991 |
| 192.108.243.0/24 | 256 | ARIN | US | 5th Aug 1991 |
| 192.108.244.0/24 | 256 | ARIN | US | 5th Aug 1991 |
| 192.108.245.0/24 | 256 | ARIN | US | 7th Mar 1996 |
| 192.108.246.0/23 | 512 | ARIN | US | 5th Aug 1991 |
| 192.108.248.0/24 | 256 | ARIN | US | 5th Aug 1991 |
| 192.108.249.0/24 | 256 | ARIN | US | 3rd Feb 1993 |
| 192.108.250.0/24 | 256 | ARIN | US | 5th Aug 1991 |
| 192.108.251.0/24 | 256 | ARIN | US | 5th Aug 1991 |
| 192.108.252.0/23 | 512 | ARIN | US | 5th Aug 1991 |
| 192.108.27.0/24 | 256 | RIPE NCC |  EU | 1st May 1991 |
| 192.108.28.0/24 | 256 | RIPE NCC | EU | 1st May 1991 |
| 192.108.29.0/24 | 256 | RIPE NCC | EU | 1st May 1991 |
| 192.108.3.0/24 | 256 | ARIN | US | 26th Apr 1991 |
| 192.108.4.0/24 | 256 | ARIN | US | 26th Apr 1991 |
| 192.108.49.0/24 | 256 | RIPE NCC |  DE | 1st May 1991 |
| 192.108.5.0/24 | 256 | ARIN | US | 26th Apr 1991 |
| 192.108.55.0/24 | 256 | RIPE NCC | DE | 1st May 1991 |
| 192.108.56.0/21 | 2k | RIPE NCC | DE | 1st May 1991 |
| 192.108.6.0/24 | 256 | ARIN | US | 26th Apr 1991 |
| 192.108.64.0/24 | 256 | RIPE NCC | DE | 1st May 1991 |
| 192.108.65.0/24 | 256 | RIPE NCC | DE | 1st May 1991 |
| 192.108.7.0/24 | 256 | ARIN | US | 26th Apr 1991 |
| 192.108.74.0/23 | 512 | RIPE NCC | DE | 1st May 1991 |
| 192.108.76.0/22 | 1k | RIPE NCC | DE | 1st May 1991 |
| 192.108.80.0/21 | 2k | RIPE NCC | DE | 1st May 1991 |
| 192.108.93.0/24 | 256 | ARIN | US | 2nd May 1991 |
| 192.108.94.0/24 | 256 | ARIN | US | 2nd May 1991 |