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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,392 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 204.68.164.0/23 | 512 | ARIN |  US | 19th Aug 1994 |
| 204.68.166.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.167.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.168.0/24 | 256 | ARIN | US | 1st Mar 2017 |
| 204.68.169.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.172.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.173.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.174.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.175.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.176.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.177.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.178.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.180.0/23 | 512 | ARIN | US | 19th Aug 1994 |
| 204.68.182.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.183.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.184.0/24 | 256 | ARIN | US | 25th Mar 2011 |
| 204.68.185.0/24 | 256 | ARIN | US | 19th Aug 1994 |
| 204.68.188.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.189.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.190.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.191.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.192.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.193.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.198.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.199.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.200.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.201.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.206.0/24 | 256 | ARIN | US | 22nd Aug 1994 |
| 204.68.208.0/24 | 256 | ARIN | US | 23rd Aug 1994 |
| 204.68.209.0/24 | 256 | ARIN | US | 23rd Aug 1994 |
| 204.68.211.0/24 | 256 | ARIN | US | 23rd Aug 1994 |
| 204.68.212.0/23 | 512 | ARIN | US | 23rd Aug 1994 |
| 204.68.214.0/24 | 256 | ARIN | US | 23rd Aug 1994 |
| 204.68.215.0/24 | 256 | ARIN | US | 23rd Aug 1994 |
| 204.68.216.0/24 | 256 | ARIN | US | 16th Jul 2018 |
| 204.68.217.0/24 | 256 | ARIN | US | 23rd Aug 1994 |
| 204.68.218.0/23 | 512 | ARIN | US | 25th Aug 1994 |
| 204.68.220.0/23 | 512 | ARIN | US | 25th Aug 1994 |
| 204.68.222.0/24 | 256 | ARIN | US | 25th Aug 1994 |
| 204.68.223.0/24 | 256 | ARIN | US | 25th Aug 1994 |
| 204.68.224.0/24 | 256 | ARIN | US | 25th Aug 1994 |
| 204.68.225.0/24 | 256 | ARIN | US | 26th Aug 1994 |
| 204.68.226.0/24 | 256 | ARIN | US | 26th Aug 1994 |
| 204.68.229.0/24 | 256 | ARIN | US | 26th Aug 1994 |
| 204.68.230.0/24 | 256 | ARIN | US | 26th Aug 1994 |
| 204.68.239.0/24 | 256 | ARIN | US | 26th Aug 1994 |
| 204.68.240.0/24 | 256 | ARIN | US | 26th Aug 1994 |
| 204.68.243.0/24 | 256 | ARIN | US | 26th Aug 1994 |
| 204.68.244.0/24 | 256 | ARIN | US | 26th Aug 1994 |
| 204.68.246.0/24 | 256 | ARIN | US | 26th Aug 1994 |