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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,285 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 199.120.222.0/24 | 256 | ARIN |  US | 8th Mar 1994 |
| 199.120.224.0/24 | 256 | ARIN | US | 8th Mar 1994 |
| 199.120.225.0/24 | 256 | ARIN | US | 21st Jun 2019 |
| 199.120.226.0/24 | 256 | ARIN | US | 8th Mar 1994 |
| 199.120.227.0/24 | 256 | ARIN | US | 8th Mar 1994 |
| 199.120.230.0/24 | 256 | RIPE NCC |  GB | 8th Mar 1994 |
| 199.120.231.0/24 | 256 | ARIN | US | 9th Mar 1994 |
| 199.120.232.0/22 | 1k | ARIN | US | 9th Mar 1994 |
| 199.120.236.0/24 | 256 | ARIN | US | 9th Mar 1994 |
| 199.120.237.0/24 | 256 | ARIN | US | 9th Mar 1994 |
| 199.120.238.0/24 | 256 | ARIN | US | 13th Oct 2015 |
| 199.120.240.0/24 | 256 | ARIN | US | 9th Mar 1994 |
| 199.120.241.0/24 | 256 | ARIN | US | 9th Mar 1994 |
| 199.120.244.0/24 | 256 | ARIN | US | 10th Mar 1994 |
| 199.120.245.0/24 | 256 | ARIN | US | 10th Mar 1994 |
| 199.120.246.0/24 | 256 | ARIN | US | 10th Mar 1994 |
| 199.120.247.0/24 | 256 | ARIN | US | 10th Mar 1994 |
| 199.120.248.0/24 | 256 | ARIN | US | 10th Mar 1994 |
| 199.120.253.0/24 | 256 | ARIN | US | 10th Mar 1994 |
| 199.120.60.0/22 | 1k | ARIN | US | 27th Mar 2009 |
| 199.120.8.0/22 | 1k | ARIN | US | 24th Jan 1994 |
| 199.121.0.0/22 | 1k | ARIN | US | 28th Jan 1994 |
| 199.121.128.0/18 | 16.4k | ARIN | US | 8th Nov 2022 |
| 199.121.16.0/20 | 4.1k | ARIN | US | 8th Nov 2022 |
| 199.121.192.0/19 | 8.2k | ARIN | US | 8th Nov 2022 |
| 199.121.224.0/20 | 4.1k | ARIN | US | 8th Nov 2022 |
| 199.121.240.0/21 | 2k | ARIN | US | 8th Nov 2022 |
| 199.121.248.0/22 | 1k | ARIN | US | 8th Nov 2022 |
| 199.121.252.0/23 | 512 | ARIN | US | 8th Nov 2022 |
| 199.121.32.0/19 | 8.2k | ARIN | US | 8th Nov 2022 |
| 199.121.4.0/22 | 1k | ARIN | US | 8th Nov 2022 |
| 199.121.64.0/18 | 16.4k | ARIN | US | 8th Nov 2022 |
| 199.121.8.0/21 | 2k | ARIN | US | 8th Nov 2022 |
| 199.122.0.0/23 | 512 | ARIN | US | 21st Feb 1994 |
| 199.122.116.0/22 | 1k | ARIN |  CA | 13th Mar 2012 |
| 199.122.2.0/24 | 256 | ARIN | US | 21st Feb 1994 |
| 199.122.6.0/24 | 256 | ARIN | US | 15th Feb 1994 |
| 199.122.7.0/24 | 256 | ARIN | CA | 10th Aug 2012 |
| 199.123.16.0/21 | 2k | ARIN | US | 21st Feb 1994 |
| 199.123.24.0/22 | 1k | ARIN | US | 21st Feb 1994 |
| 199.123.28.0/23 | 512 | ARIN | US | 21st Feb 1994 |
| 199.125.0.0/21 | 2k | ARIN | US | 27th Jan 1994 |
| 199.125.32.0/21 | 2k | ARIN | US | 15th Apr 1994 |
| 199.125.40.0/22 | 1k | ARIN | US | 15th Apr 1994 |
| 199.125.46.0/23 | 512 | ARIN | US | 15th Apr 1994 |
| 199.127.0.0/21 | 2k | ARIN | US | 2nd Feb 1994 |
| 199.127.130.0/23 | 512 | ARIN | US | 8th Apr 2025 |
| 199.127.16.0/21 | 2k | ARIN | US | 18th Nov 1993 |
| 199.127.204.0/22 | 1k | ARIN | US | 27th May 2011 |
| 199.127.224.0/22 | 1k | ARIN | US | 1st Jun 2011 |