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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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.
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Countries with unannounced space registered through ARIN, largest first.
Unannounced blocks registered through ARIN
30,430 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 142.175.0.0/16 | 65.5k | ARIN |  CA | 26th Aug 1992 |
| 142.178.0.0/16 | 65.5k | ARIN | CA | 26th Aug 1992 |
| 142.193.0.0/16 | 65.5k | ARIN | CA | 18th Jan 1994 |
| 142.2.0.0/16 | 65.5k | ARIN | CA | 21st Sept 1990 |
| 142.202.106.0/24 | 256 | ARIN |  US | 20th Dec 2019 |
| 142.202.12.0/22 | 1k | ARIN | CA | 18th Dec 2019 |
| 142.202.155.0/24 | 256 | ARIN | US | 26th Jun 2024 |
| 142.202.156.0/24 | 256 | ARIN | US | 21st Jan 2020 |
| 142.202.159.0/24 | 256 | ARIN | US | 8th Jan 2020 |
| 142.202.176.0/22 | 1k | ARIN | US | 4th Feb 2020 |
| 142.202.184.0/24 | 256 | ARIN | US | 18th Dec 2019 |
| 142.202.199.0/24 | 256 | ARIN | US | 8th Jan 2020 |
| 142.202.236.0/22 | 1k | ARIN | US | 27th Dec 2019 |
| 142.202.4.0/22 | 1k | ARIN | US | 18th Dec 2019 |
| 142.202.66.0/24 | 256 | ARIN | US | 14th Jan 2020 |
| 142.202.8.0/24 | 256 | ARIN | US | 19th Dec 2019 |
| 142.202.81.0/24 | 256 | ARIN | US | 19th Dec 2019 |
| 142.202.89.0/24 | 256 | ARIN | US | 20th Dec 2019 |
| 142.208.0.0/16 | 65.5k | ARIN | CA | 26th Oct 1992 |
| 142.209.0.0/16 | 65.5k | ARIN | CA | 26th Oct 1992 |
| 142.210.0.0/16 | 65.5k | ARIN | CA | 26th Oct 1992 |
| 142.211.0.0/16 | 65.5k | ARIN | CA | 26th Oct 1992 |
| 142.212.0.0/16 | 65.5k | ARIN | CA | 27th Oct 1992 |
| 142.218.0.0/16 | 65.5k | ARIN | CA | 15th Oct 1993 |
| 142.220.0.0/16 | 65.5k | ARIN | CA | 28th Oct 1992 |
| 142.223.0.0/16 | 65.5k | ARIN | CA | 10th Mar 1993 |
| 142.224.0.0/16 | 65.5k | ARIN | CA | 24th Mar 1994 |
| 142.226.0.0/16 | 65.5k | ARIN | CA | 18th Oct 1993 |
| 142.228.0.0/23 | 512 | ARIN | CA | 30th Dec 1992 |
| 142.228.128.0/17 | 32.8k | ARIN | CA | 30th Dec 1992 |
| 142.228.16.0/20 | 4.1k | ARIN | CA | 30th Dec 1992 |
| 142.228.2.0/23 | 512 | ARIN | CA | 17th Aug 2026 |
| 142.228.32.0/21 | 2k | ARIN | CA | 30th Dec 1992 |
| 142.228.4.0/22 | 1k | ARIN | CA | 30th Dec 1992 |
| 142.228.40.0/22 | 1k | ARIN | CA | 30th Dec 1992 |
| 142.228.44.0/23 | 512 | ARIN | CA | 30th Dec 1992 |
| 142.228.46.0/23 | 512 | ARIN | CA | 12th Aug 2026 |
| 142.228.48.0/22 | 1k | ARIN | US | 11th Aug 2026 |
| 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 |