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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 199.196.192.0/19 | 8.2k | ARIN |  US | 16th Feb 1995 |
| 199.196.32.0/19 | 8.2k | ARIN | US | 28th Mar 1994 |
| 199.196.4.0/24 | 256 | ARIN | US | 29th Mar 1994 |
| 199.196.5.0/24 | 256 | ARIN | US | 6th Jun 2012 |
| 199.196.64.0/18 | 16.4k | ARIN | US | 7th Apr 1994 |
| 199.198.140.0/22 | 1k | ARIN |  CA | 25th Mar 1994 |
| 199.198.160.0/20 | 4.1k | ARIN | CA | 25th Mar 1994 |
| 199.198.176.0/21 | 2k | ARIN | CA | 25th Mar 1994 |
| 199.198.184.0/23 | 512 | ARIN | CA | 25th Mar 1994 |
| 199.198.186.0/24 | 256 | ARIN | CA | 13th Apr 2011 |
| 199.198.187.0/24 | 256 | ARIN | CA | 25th Mar 1994 |
| 199.198.188.0/22 | 1k | ARIN | CA | 25th Mar 1994 |
| 199.198.192.0/20 | 4.1k | ARIN | CA | 25th Mar 1994 |
| 199.198.208.0/23 | 512 | ARIN | CA | 25th Mar 1994 |
| 199.198.214.0/23 | 512 | ARIN | US | 16th Jul 2015 |
| 199.198.218.0/24 | 256 | ARIN | CA | 14th Mar 1994 |
| 199.198.240.0/21 | 2k | ARIN | US | 22nd Mar 1994 |
| 199.198.252.0/23 | 512 | ARIN | US | 22nd Mar 1994 |
| 199.198.255.0/24 | 256 | ARIN | US | 11th Jun 2012 |
| 199.200.0.0/22 | 1k | ARIN | US | 7th Apr 1994 |
| 199.200.12.0/23 | 512 | ARIN | US | 1st Apr 1994 |
| 199.200.128.0/18 | 16.4k | ARIN | US | 9th Feb 1995 |
| 199.200.14.0/23 | 512 | ARIN | US | 21st Jul 2015 |
| 199.200.4.0/24 | 256 | ARIN | US | 7th Apr 1994 |
| 199.200.8.0/22 | 1k | ARIN | US | 1st Apr 1994 |
| 199.200.96.0/22 | 1k | ARIN | US | 8th Jun 2012 |
| 199.201.121.0/24 | 256 | ARIN | CA | 14th Aug 2019 |
| 199.201.127.0/24 | 256 | ARIN | US | 7th Feb 2020 |
| 199.201.129.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.130.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.132.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.133.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.134.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.135.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.136.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.138.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.140.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.141.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.142.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.143.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.144.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.146.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.147.0/24 | 256 | ARIN | US | 28th Apr 1994 |
| 199.201.148.0/24 | 256 | ARIN | US | 29th Apr 1994 |
| 199.201.149.0/24 | 256 | ARIN | US | 29th Apr 1994 |
| 199.201.150.0/24 | 256 | ARIN | US | 29th Apr 1994 |
| 199.201.151.0/24 | 256 | ARIN | US | 29th Apr 1994 |
| 199.201.152.0/24 | 256 | ARIN | US | 29th Apr 1994 |
| 199.201.16.0/22 | 1k | ARIN | US | 18th Mar 1994 |
| 199.201.160.0/24 | 256 | ARIN | US | 29th Apr 1994 |