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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 192.16.229.0/24 | 256 | ARIN |  CA | 14th Mar 1991 |
| 192.16.230.0/24 | 256 | ARIN | CA | 14th Mar 1991 |
| 192.16.231.0/24 | 256 | ARIN | CA | 14th Mar 1991 |
| 192.16.232.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.233.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.234.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.235.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.236.0/24 | 256 | ARIN | CA | 29th Oct 1992 |
| 192.16.237.0/24 | 256 | ARIN | CA | 29th Oct 1992 |
| 192.16.238.0/24 | 256 | ARIN | CA | 29th Oct 1992 |
| 192.16.239.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.240.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.241.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.242.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.243.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.244.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.245.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.246.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.247.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.248.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.249.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.252.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.253.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.254.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.16.255.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.169.4.0/24 | 256 | ARIN | CA | 3rd Oct 2022 |
| 192.171.114.0/23 | 512 | ARIN | CA | 17th Mar 2015 |
| 192.172.254.0/24 | 256 | ARIN | CA | 11th Jun 1992 |
| 192.188.168.0/24 | 256 | ARIN | CA | 20th Jul 1992 |
| 192.188.169.0/24 | 256 | ARIN | CA | 20th Jul 1992 |
| 192.189.0.0/24 | 256 | ARIN | CA | 3rd Oct 2025 |
| 192.189.22.0/24 | 256 | ARIN | CA | 18th Jun 1992 |
| 192.189.67.0/24 | 256 | ARIN | CA | 10th Jul 1992 |
| 192.189.68.0/24 | 256 | ARIN | CA | 10th Jul 1992 |
| 192.190.19.0/24 | 256 | ARIN | CA | 12th Jul 2019 |
| 192.190.25.0/24 | 256 | ARIN | CA | 31st Jul 2020 |
| 192.197.112.0/24 | 256 | ARIN | CA | 19th Jul 1992 |
| 192.197.116.0/24 | 256 | ARIN | CA | 27th Nov 1992 |
| 192.197.117.0/24 | 256 | ARIN | CA | 27th Nov 1992 |
| 192.197.118.0/24 | 256 | ARIN | CA | 27th Nov 1992 |
| 192.197.119.0/24 | 256 | ARIN | CA | 27th Nov 1992 |
| 192.197.133.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.197.134.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.197.138.0/24 | 256 | ARIN | CA | 21st Sept 1993 |
| 192.197.139.0/24 | 256 | ARIN | CA | 17th Mar 1993 |
| 192.197.140.0/24 | 256 | ARIN | CA | 4th Dec 1992 |
| 192.197.141.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 192.197.143.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 192.197.149.0/24 | 256 | ARIN | CA | 11th Dec 1992 |
| 192.197.150.0/24 | 256 | ARIN | CA | 11th Dec 1992 |