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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 in Canada
3,830 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 142.228.135.0/24 | 256 | ARIN |  CA | 30th Dec 1992 |
| 142.228.150.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 142.228.153.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 142.228.170.0/23 | 512 | ARIN | CA | 30th Dec 1992 |
| 142.228.180.0/23 | 512 | ARIN | CA | 30th Dec 1992 |
| 142.228.2.0/23 | 512 | ARIN | CA | 17th Aug 2026 |
| 142.228.25.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 142.228.29.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 142.228.31.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 142.228.35.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 142.228.44.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 142.228.58.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 142.228.59.0/24 | 256 | ARIN | CA | 16th Oct 2026 |
| 142.228.66.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 142.228.73.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 142.228.88.0/23 | 512 | ARIN | CA | 30th Dec 1992 |
| 142.235.0.0/16 | 65.5k | ARIN | CA | 6th May 1993 |
| 142.248.12.0/22 | 1k | ARIN | CA | 10th Oct 2025 |
| 142.248.60.0/23 | 512 | ARIN | CA | 20th Oct 2025 |
| 142.249.124.0/24 | 256 | ARIN | CA | 9th Oct 2025 |
| 142.253.0.0/16 | 65.5k | ARIN | CA | 11th Aug 1993 |
| 142.37.0.0/16 | 65.5k | ARIN | CA | 9th Apr 1991 |
| 142.38.0.0/16 | 65.5k | ARIN | CA | 9th Apr 1991 |
| 142.42.0.0/16 | 65.5k | ARIN | CA | 26th Feb 1993 |
| 142.45.0.0/16 | 65.5k | ARIN | CA | 26th Mar 1990 |
| 142.5.0.0/16 | 65.5k | ARIN | CA | 30th Jun 1990 |
| 142.50.0.0/16 | 65.5k | ARIN | CA | 26th Mar 1990 |
| 142.53.0.0/16 | 65.5k | ARIN | CA | 13th May 1991 |
| 142.62.0.0/16 | 65.5k | ARIN | CA | 18th Jun 1991 |
| 142.63.0.0/16 | 65.5k | ARIN | CA | 18th Jun 1991 |
| 142.67.16.0/21 | 2k | ARIN | CA | 28th Jun 1991 |
| 142.67.24.0/22 | 1k | ARIN | CA | 28th Jun 1991 |
| 142.67.32.0/19 | 8.2k | ARIN | CA | 28th Jun 1991 |
| 142.69.0.0/16 | 65.5k | ARIN | CA | 11th Jul 1991 |
| 142.7.0.0/16 | 65.5k | ARIN | CA | 30th Nov 1990 |
| 142.71.0.0/16 | 65.5k | ARIN | CA | 26th Mar 1990 |
| 142.72.0.0/16 | 65.5k | ARIN | CA | 6th Jun 1994 |
| 142.8.0.0/16 | 65.5k | ARIN | CA | 30th Nov 1990 |
| 142.95.0.0/16 | 65.5k | ARIN | CA | 3rd Jan 1992 |
| 142.96.0.0/16 | 65.5k | ARIN | CA | 3rd Jan 1992 |
| 142.97.0.0/16 | 65.5k | ARIN | CA | 26th Mar 1990 |
| 142.99.104.0/23 | 512 | ARIN | CA | 7th Jan 1992 |
| 142.99.112.0/20 | 4.1k | ARIN | CA | 7th Jan 1992 |
| 142.99.16.0/22 | 1k | ARIN | CA | 7th Jan 1992 |
| 142.99.32.0/19 | 8.2k | ARIN | CA | 7th Jan 1992 |
| 142.99.64.0/19 | 8.2k | ARIN | CA | 7th Jan 1992 |
| 143.203.0.0/22 | 1k | ARIN | CA | 2nd Oct 2026 |
| 143.203.56.0/22 | 1k | ARIN | CA | 2nd Oct 2026 |
| 143.203.96.0/22 | 1k | ARIN | CA | 2nd Oct 2026 |
| 147.160.148.0/24 | 256 | ARIN | CA | 9th Sept 2019 |