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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 199.249.194.0/24 | 256 | ARIN |  US | 2nd Jun 1994 |
| 199.249.198.0/24 | 256 | ARIN | US | 2nd Jun 1994 |
| 199.249.200.0/24 | 256 | ARIN | US | 2nd Jun 1994 |
| 199.249.201.0/24 | 256 | ARIN | US | 2nd Jun 1994 |
| 199.249.202.0/24 | 256 | ARIN | US | 2nd Jun 1994 |
| 199.249.203.0/24 | 256 | ARIN | US | 2nd Jun 1994 |
| 199.249.204.0/24 | 256 | ARIN | US | 2nd Jun 1994 |
| 199.249.206.0/24 | 256 | ARIN | US | 2nd Jun 1994 |
| 199.249.215.0/24 | 256 | ARIN | US | 2nd Jun 1994 |
| 199.249.218.0/23 | 512 | ARIN | US | 3rd Jun 1994 |
| 199.249.220.0/23 | 512 | ARIN | US | 3rd Jun 1994 |
| 199.249.226.0/24 | 256 | ARIN | US | 6th Jun 1994 |
| 199.249.229.0/24 | 256 | ARIN | US | 6th Jun 1994 |
| 199.249.237.0/24 | 256 | ARIN | US | 7th Jun 1994 |
| 199.249.240.0/24 | 256 | ARIN | US | 7th Jun 1994 |
| 199.249.241.0/24 | 256 | ARIN | US | 7th Jun 1994 |
| 199.249.242.0/24 | 256 | ARIN | US | 7th Jun 1994 |
| 199.249.244.0/23 | 512 | ARIN | US | 7th Jun 1994 |
| 199.249.246.0/24 | 256 | ARIN | US | 8th Jun 1994 |
| 199.249.247.0/24 | 256 | ARIN | US | 8th Jun 1994 |
| 199.249.248.0/24 | 256 | ARIN | US | 8th Jun 1994 |
| 199.249.249.0/24 | 256 | ARIN | US | 8th Jun 1994 |
| 199.249.250.0/23 | 512 | ARIN | US | 8th Jun 1994 |
| 199.249.252.0/24 | 256 | ARIN | US | 8th Jun 1994 |
| 199.249.254.0/24 | 256 | ARIN | US | 8th Jun 1994 |
| 199.249.64.0/19 | 8.2k | ARIN | US | 20th May 1994 |
| 199.249.96.0/21 | 2k | ARIN | US | 20th May 1994 |
| 199.250.190.0/23 | 512 | ARIN | US | 27th May 1994 |
| 199.250.255.0/24 | 256 | ARIN | US | 21st Feb 2018 |
| 199.253.144.0/21 | 2k | ARIN | US | 24th Jan 1995 |
| 199.253.152.0/21 | 2k | ARIN | US | 24th Jan 1995 |
| 199.253.160.0/21 | 2k | ARIN | US | 24th Jan 1995 |
| 199.253.192.0/21 | 2k | ARIN | US | 21st Feb 1995 |
| 199.253.208.0/22 | 1k | ARIN | US | 22nd Feb 1995 |
| 199.253.212.0/23 | 512 | ARIN | US | 22nd Feb 1995 |
| 199.253.242.0/23 | 512 | ARIN | US | 2nd Mar 1995 |
| 199.253.248.0/24 | 256 | ARIN | US | 2nd Mar 1995 |
| 199.253.32.0/20 | 4.1k | ARIN | US | 5th May 1994 |
| 199.253.48.0/21 | 2k | ARIN | US | 5th May 1994 |
| 199.253.62.0/24 | 256 | ARIN | US | 9th Sept 2008 |
| 199.253.64.0/19 | 8.2k | ARIN | US | 16th Sept 1994 |
| 199.254.104.0/21 | 2k | ARIN |  BB | 17th Aug 2012 |
| 199.254.128.0/24 | 256 | ARIN | US | 13th Oct 1994 |
| 199.254.129.0/24 | 256 | ARIN | US | 13th Oct 1994 |
| 199.254.130.0/24 | 256 | ARIN | US | 13th Oct 1994 |
| 199.254.131.0/24 | 256 | ARIN | US | 13th Oct 1994 |
| 199.254.132.0/24 | 256 | ARIN | US | 13th Oct 1994 |
| 199.254.134.0/24 | 256 | ARIN | US | 13th Oct 1994 |
| 199.254.136.0/24 | 256 | ARIN | US | 13th Oct 1994 |
| 199.254.137.0/24 | 256 | ARIN | US | 13th Oct 1994 |