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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,041 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 167.22.0.0/16 | 65.5k | ARIN |  US | 20th Apr 1993 |
| 167.221.0.0/16 | 65.5k | ARIN | US | 21st Oct 1993 |
| 167.224.48.0/21 | 2k | ARIN | US | 25th Oct 1993 |
| 167.224.68.0/22 | 1k | ARIN | US | 25th Oct 1993 |
| 167.224.72.0/21 | 2k | ARIN | US | 25th Oct 1993 |
| 167.226.0.0/16 | 65.5k | ARIN | US | 1st Jun 2018 |
| 167.228.0.0/16 | 65.5k | ARIN | US | 1st Nov 1993 |
| 167.234.0.0/19 | 8.2k | ARIN | US | 7th Aug 2026 |
| 167.234.32.0/22 | 1k | ARIN | US | 10th Nov 1993 |
| 167.234.37.0/24 | 256 | ARIN | US | 1st Jul 2026 |
| 167.247.128.0/17 | 32.8k | ARIN | US | 19th Nov 1993 |
| 167.247.64.0/20 | 4.1k | ARIN | US | 19th Nov 1993 |
| 167.248.128.0/22 | 1k | ARIN | US | 24th Nov 1993 |
| 167.248.132.0/24 | 256 | ARIN | US | 24th Nov 1993 |
| 167.250.84.0/22 | 1k | LACNIC |  BR | 14th Dec 2015 |
| 167.252.0.0/16 | 65.5k | LACNIC |  AR | 26th Nov 1993 |
| 167.253.110.0/24 | 256 | ARIN | US | 3rd Apr 2024 |
| 167.253.152.0/22 | 1k | ARIN | US | 6th May 2024 |
| 167.253.192.0/18 | 16.4k | ARIN | US | 14th Jan 2000 |
| 167.253.28.0/24 | 256 | ARIN | US | 13th Jan 2026 |
| 167.253.31.0/24 | 256 | ARIN |  CA | 4th Apr 2024 |
| 167.253.4.0/22 | 1k | ARIN | CA | 9th Apr 2024 |
| 167.253.40.0/22 | 1k | ARIN | US | 4th Apr 2024 |
| 167.253.46.0/24 | 256 | ARIN | US | 3rd Apr 2024 |
| 167.253.56.0/24 | 256 | ARIN | US | 4th Apr 2024 |
| 167.253.59.0/24 | 256 | ARIN | US | 4th Apr 2024 |
| 167.253.76.0/23 | 512 | ARIN | CA | 10th Apr 2024 |
| 167.254.112.0/20 | 4.1k | ARIN | US | 10th Apr 2026 |
| 167.254.144.0/21 | 2k | ARIN | US | 26th Jan 2026 |
| 167.254.152.0/21 | 2k | ARIN | US | 20th Feb 2026 |
| 167.254.248.0/22 | 1k | ARIN |  FR | 4th Mar 2026 |
| 167.254.80.0/20 | 4.1k | ARIN | US | 23rd Jan 2026 |
| 167.255.0.0/16 | 65.5k | ARIN | US | 30th Nov 1993 |
| 167.26.0.0/16 | 65.5k | ARIN | US | 29th Apr 1993 |
| 167.27.0.0/16 | 65.5k | ARIN | US | 29th Apr 1993 |
| 167.31.0.0/16 | 65.5k | ARIN | US | 4th May 1993 |
| 167.33.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.34.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.35.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.36.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.38.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.39.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.41.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.42.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.45.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.47.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.48.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.49.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |
| 167.5.0.0/16 | 65.5k | ARIN | US | 7th Apr 1993 |
| 167.50.0.0/16 | 65.5k | ARIN | CA | 25th Mar 1993 |