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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
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Countries with the most unannounced blocks, largest first.
Unannounced blocks
84,968 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 142.228.48.0/22 | 1k | ARIN |  US | 11th Aug 2026 |
| 142.228.52.0/22 | 1k | RIPE NCC |  FI | 30th Dec 1992 |
| 142.228.56.0/21 | 2k | ARIN |  CA | 30th Dec 1992 |
| 142.228.64.0/18 | 16.4k | ARIN | CA | 30th Dec 1992 |
| 142.228.8.0/21 | 2k | ARIN | CA | 30th Dec 1992 |
| 142.235.0.0/16 | 65.5k | ARIN | CA | 6th May 1993 |
| 142.248.108.0/23 | 512 | ARIN | US | 14th Oct 2025 |
| 142.248.110.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.112.0/22 | 1k | ARIN | US | 14th Oct 2025 |
| 142.248.12.0/22 | 1k | ARIN | CA | 10th Oct 2025 |
| 142.248.127.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.132.0/22 | 1k | ARIN | US | 10th Oct 2025 |
| 142.248.156.0/24 | 256 | ARIN | CA | 10th Oct 2025 |
| 142.248.158.0/24 | 256 | ARIN | US | 13th Jan 2026 |
| 142.248.164.0/22 | 1k | ARIN | US | 10th Oct 2025 |
| 142.248.168.0/22 | 1k | ARIN | US | 13th Oct 2025 |
| 142.248.189.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.196.0/22 | 1k | ARIN | US | 10th Oct 2025 |
| 142.248.204.0/23 | 512 | ARIN | US | 10th Oct 2025 |
| 142.248.206.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.207.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.208.0/22 | 1k | ARIN | US | 10th Oct 2025 |
| 142.248.220.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.223.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.24.0/22 | 1k | ARIN | US | 10th Oct 2025 |
| 142.248.248.0/23 | 512 | ARIN |  BS | 10th Oct 2025 |
| 142.248.250.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.251.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.252.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.253.0/24 | 256 | ARIN | US | 16th Jan 2026 |
| 142.248.254.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.255.0/24 | 256 | ARIN | US | 13th Jan 2026 |
| 142.248.36.0/23 | 512 | ARIN | US | 12th Nov 2025 |
| 142.248.39.0/24 | 256 | ARIN | US | 17th Oct 2025 |
| 142.248.4.0/22 | 1k | ARIN | US | 10th Oct 2025 |
| 142.248.47.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.48.0/22 | 1k | ARIN | US | 10th Oct 2025 |
| 142.248.60.0/23 | 512 | ARIN | CA | 20th Oct 2025 |
| 142.248.63.0/24 | 256 | ARIN | US | 10th Oct 2025 |
| 142.248.72.0/22 | 1k | ARIN | US | 10th Oct 2025 |
| 142.248.76.0/22 | 1k | ARIN | US | 10th Oct 2025 |
| 142.248.92.0/23 | 512 | ARIN | US | 10th Oct 2025 |
| 142.248.95.0/24 | 256 | ARIN | US | 14th Oct 2025 |
| 142.249.108.0/23 | 512 | ARIN | US | 9th Oct 2025 |
| 142.249.110.0/24 | 256 | ARIN | US | 25th Nov 2025 |
| 142.249.116.0/22 | 1k | ARIN | US | 9th Oct 2025 |
| 142.249.124.0/24 | 256 | ARIN | CA | 9th Oct 2025 |
| 142.249.126.0/24 | 256 | ARIN | US | 9th Oct 2025 |
| 142.249.132.0/22 | 1k | ARIN | US | 9th Oct 2025 |
| 142.249.152.0/24 | 256 | ARIN | US | 9th Oct 2025 |