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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,285 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 199.190.173.0/24 | 256 | ARIN |  US | 25th Apr 1994 |
| 199.190.176.0/23 | 512 | ARIN | US | 25th Apr 1994 |
| 199.190.178.0/23 | 512 | ARIN | US | 25th Apr 1994 |
| 199.190.180.0/24 | 256 | ARIN | US | 25th Apr 1994 |
| 199.190.181.0/24 | 256 | ARIN | US | 25th Apr 1994 |
| 199.190.182.0/24 | 256 | ARIN | US | 25th Apr 1994 |
| 199.190.186.0/24 | 256 | ARIN | US | 25th Apr 1994 |
| 199.190.187.0/24 | 256 | ARIN | US | 25th Apr 1994 |
| 199.190.188.0/24 | 256 | ARIN | US | 25th Apr 1994 |
| 199.190.189.0/24 | 256 | ARIN | US | 25th Apr 1994 |
| 199.190.190.0/24 | 256 | ARIN | US | 26th Apr 1994 |
| 199.190.192.0/24 | 256 | ARIN | US | 26th Apr 1994 |
| 199.190.193.0/24 | 256 | ARIN | US | 26th Apr 1994 |
| 199.190.194.0/23 | 512 | ARIN | US | 20th Jul 2015 |
| 199.190.198.0/23 | 512 | ARIN | US | 27th Apr 1994 |
| 199.190.200.0/24 | 256 | ARIN | US | 27th Apr 1994 |
| 199.190.201.0/24 | 256 | ARIN | US | 27th Apr 1994 |
| 199.190.202.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.203.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.204.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.205.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.206.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.207.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.208.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.209.0/24 | 256 | ARIN | US | 17th Sept 2015 |
| 199.190.210.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.212.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.213.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.214.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.215.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.216.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.217.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.218.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.219.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.220.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.221.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.227.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.231.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.232.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.233.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.234.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.235.0/24 | 256 | ARIN | US | 8th Apr 2019 |
| 199.190.236.0/24 | 256 | ARIN | US | 8th Apr 2019 |
| 199.190.240.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.190.243.0/24 | 256 | ARIN | US | 12th May 1994 |
| 199.190.244.0/22 | 1k | ARIN | US | 12th May 1994 |
| 199.190.248.0/24 | 256 | ARIN | US | 12th May 1994 |
| 199.190.253.0/24 | 256 | ARIN | US | 12th May 1994 |
| 199.190.254.0/24 | 256 | ARIN | US | 13th May 1994 |
| 199.190.32.0/21 | 2k | ARIN | US | 23rd May 1994 |