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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 199.242.167.0/24 | 256 | ARIN |  US | 11th May 1994 |
| 199.242.169.0/24 | 256 | ARIN | US | 11th May 1994 |
| 199.242.170.0/23 | 512 | ARIN | US | 11th May 1994 |
| 199.242.172.0/24 | 256 | ARIN | US | 11th May 1994 |
| 199.242.173.0/24 | 256 | ARIN | US | 11th May 1994 |
| 199.242.175.0/24 | 256 | ARIN | US | 11th May 1994 |
| 199.242.179.0/24 | 256 | ARIN | US | 11th May 1994 |
| 199.242.180.0/23 | 512 | ARIN | US | 28th Jul 2015 |
| 199.242.193.0/24 | 256 | ARIN | US | 13th May 1994 |
| 199.242.194.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.195.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.196.0/22 | 1k | ARIN | US | 14th May 1994 |
| 199.242.200.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.201.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.202.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.204.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.205.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.208.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.210.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.214.0/24 | 256 | ARIN | US | 2nd Oct 2025 |
| 199.242.215.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.216.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.217.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.218.0/24 | 256 | ARIN | US | 14th May 1994 |
| 199.242.220.0/24 | 256 | ARIN | US | 16th May 1994 |
| 199.242.221.0/24 | 256 | ARIN | US | 16th May 1994 |
| 199.242.222.0/24 | 256 | ARIN | US | 21st Sept 2018 |
| 199.242.224.0/24 | 256 | ARIN | US | 16th May 1994 |
| 199.242.225.0/24 | 256 | ARIN | US | 16th May 1994 |
| 199.242.226.0/24 | 256 | ARIN | US | 16th May 1994 |
| 199.242.227.0/24 | 256 | ARIN | US | 16th May 1994 |
| 199.242.228.0/24 | 256 | ARIN | US | 16th May 1994 |
| 199.242.229.0/24 | 256 | ARIN | US | 16th May 1994 |
| 199.242.230.0/24 | 256 | ARIN | US | 16th May 1994 |
| 199.242.240.0/23 | 512 | ARIN | US | 17th May 1994 |
| 199.242.243.0/24 | 256 | ARIN | US | 17th May 1994 |
| 199.242.246.0/24 | 256 | ARIN | US | 17th May 1994 |
| 199.242.247.0/24 | 256 | ARIN | US | 17th May 1994 |
| 199.242.248.0/24 | 256 | ARIN | US | 17th May 1994 |
| 199.242.251.0/24 | 256 | ARIN | US | 17th May 1994 |
| 199.242.252.0/24 | 256 | ARIN | US | 17th May 1994 |
| 199.242.254.0/24 | 256 | ARIN | US | 25th May 1994 |
| 199.242.8.0/21 | 2k | ARIN | US | 29th Apr 1994 |
| 199.244.130.0/24 | 256 | ARIN | US | 10th Aug 1994 |
| 199.244.131.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 199.244.133.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 199.244.134.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 199.244.135.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 199.244.136.0/24 | 256 | ARIN | US | 12th Aug 1994 |
| 199.244.137.0/24 | 256 | ARIN | US | 12th Aug 1994 |