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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 unannounced space registered through ARIN, largest first.
Unannounced blocks in Canada
3,775 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 204.29.161.0/24 | 256 | ARIN |  CA | 22nd Jun 1994 |
| 204.29.195.0/24 | 256 | ARIN | CA | 1st Jul 2026 |
| 204.63.174.0/23 | 512 | ARIN | CA | 30th Oct 2017 |
| 204.69.208.0/24 | 256 | ARIN | CA | 24th Aug 1994 |
| 204.77.206.0/24 | 256 | ARIN | CA | 6th Oct 2011 |
| 204.79.129.0/24 | 256 | ARIN | CA | 14th Dec 1994 |
| 204.79.165.0/24 | 256 | ARIN | CA | 14th Dec 1994 |
| 204.79.224.0/23 | 512 | ARIN | CA | 19th Dec 1994 |
| 204.79.244.0/23 | 512 | ARIN | CA | 19th Dec 1994 |
| 204.8.237.0/24 | 256 | ARIN | CA | 27th Nov 2023 |
| 204.87.129.0/24 | 256 | ARIN | CA | 9th Dec 1994 |
| 204.9.160.0/21 | 2k | ARIN | CA | 21st Oct 2004 |
| 205.142.224.0/22 | 1k | ARIN | CA | 12th Sept 1995 |
| 205.151.100.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.101.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.102.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.103.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.104.0/23 | 512 | ARIN | CA | 28th Feb 1995 |
| 205.151.106.0/23 | 512 | ARIN | CA | 28th Feb 1995 |
| 205.151.108.0/22 | 1k | ARIN | CA | 28th Feb 1995 |
| 205.151.121.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.122.0/23 | 512 | ARIN | CA | 28th Feb 1995 |
| 205.151.128.0/19 | 8.2k | ARIN | CA | 28th Feb 1995 |
| 205.151.160.0/23 | 512 | ARIN | CA | 28th Feb 1995 |
| 205.151.164.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.165.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.166.0/23 | 512 | ARIN | CA | 28th Feb 1995 |
| 205.151.169.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.170.0/23 | 512 | ARIN | CA | 28th Feb 1995 |
| 205.151.172.0/22 | 1k | ARIN | CA | 28th Feb 1995 |
| 205.151.176.0/23 | 512 | ARIN | CA | 28th Feb 1995 |
| 205.151.178.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.180.0/22 | 1k | ARIN | CA | 28th Feb 1995 |
| 205.151.184.0/23 | 512 | ARIN | CA | 28th Feb 1995 |
| 205.151.186.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.187.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.188.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.190.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.191.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.20.0/22 | 1k | ARIN | CA | 21st Apr 1995 |
| 205.151.214.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.215.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.216.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.217.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.218.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.219.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.220.0/23 | 512 | ARIN | CA | 28th Feb 1995 |
| 205.151.225.0/24 | 256 | ARIN | CA | 28th Feb 1995 |
| 205.151.24.0/21 | 2k | ARIN | CA | 21st Apr 1995 |
| 205.151.247.0/24 | 256 | ARIN | CA | 28th Feb 1995 |