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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,458 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 204.225.114.0/24 | 256 | ARIN |  CA | 10th Jan 1995 |
| 204.225.115.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.116.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.117.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.118.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.120.0/24 | 256 | ARIN |  US | 1st Jul 2022 |
| 204.225.121.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.132.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.133.0/24 | 256 | ARIN | US | 10th Jan 1995 |
| 204.225.137.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.138.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.139.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.140.0/23 | 512 | ARIN | CA | 10th Jan 1995 |
| 204.225.143.0/24 | 256 | ARIN | CA | 10th Jan 1994 |
| 204.225.148.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.149.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.151.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.153.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.154.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.155.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.156.0/23 | 512 | ARIN | CA | 10th Jan 1995 |
| 204.225.160.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.161.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.162.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.164.0/23 | 512 | ARIN | CA | 10th Jan 1995 |
| 204.225.166.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.167.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.168.0/22 | 1k | ARIN | CA | 10th Jan 1995 |
| 204.225.172.0/24 | 256 | ARIN | US | 10th Jan 1995 |
| 204.225.176.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.179.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.180.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.181.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.182.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.183.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.184.0/23 | 512 | ARIN | CA | 10th Jan 1995 |
| 204.225.186.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.187.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.191.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.192.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.193.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.194.0/23 | 512 | ARIN | CA | 10th Jan 1995 |
| 204.225.196.0/22 | 1k | ARIN | CA | 10th Jan 1995 |
| 204.225.200.0/21 | 2k | ARIN | CA | 10th Jan 1994 |
| 204.225.211.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.216.0/23 | 512 | ARIN | CA | 10th Jan 1995 |
| 204.225.219.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.222.0/24 | 256 | ARIN | CA | 10th Jan 1994 |
| 204.225.225.0/24 | 256 | ARIN | CA | 10th Jan 1995 |
| 204.225.226.0/23 | 512 | ARIN | CA | 10th Jan 1995 |