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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 205.189.221.0/24 | 256 | ARIN |  CA | 22nd Mar 1995 |
| 205.189.222.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.224.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.226.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.228.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.230.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.232.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.233.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.234.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.236.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.238.0/23 | 512 | ARIN |  US | 22nd Mar 1995 |
| 205.189.248.0/22 | 1k | ARIN | CA | 22nd Mar 1995 |
| 205.189.252.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.254.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.34.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.39.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.4.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.43.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.46.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.50.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.52.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.54.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.55.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.60.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.61.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.62.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.63.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.64.0/23 | 512 | ARIN | CA | 27th Mar 1995 |
| 205.189.66.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.67.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.69.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.70.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.71.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.72.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.74.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.77.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.78.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.80.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.81.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.82.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.83.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.84.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.85.0/24 | 256 | ARIN | US | 22nd Mar 1995 |
| 205.189.86.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.89.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.92.0/23 | 512 | ARIN | CA | 22nd Mar 1995 |
| 205.189.96.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.97.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.189.98.0/24 | 256 | ARIN | CA | 22nd Mar 1995 |
| 205.190.0.0/16 | 65.5k | ARIN | US | 22nd Mar 1995 |