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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,310 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 199.33.197.0/24 | 256 | ARIN |  US | 12th Jan 1994 |
| 199.33.198.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.33.199.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.33.200.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.33.201.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.33.202.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.33.203.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.33.204.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.33.205.0/24 | 256 | ARIN | US | 12th Jan 1994 |
| 199.33.206.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 199.33.207.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 199.33.208.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 199.33.209.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 199.33.211.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 199.33.212.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 199.33.213.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 199.33.214.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 199.33.215.0/24 | 256 | ARIN | US | 13th Jan 1994 |
| 199.33.216.0/24 | 256 | ARIN | US | 14th Jan 1994 |
| 199.33.217.0/24 | 256 | ARIN | US | 14th Jan 1994 |
| 199.33.220.0/23 | 512 | ARIN | US | 14th Jan 1994 |
| 199.33.222.0/24 | 256 | ARIN | US | 20th Jan 1994 |
| 199.33.223.0/24 | 256 | ARIN | US | 20th Jan 1994 |
| 199.33.228.0/24 | 256 | ARIN | US | 20th Jan 1994 |
| 199.33.229.0/24 | 256 | ARIN | US | 20th Jan 1994 |
| 199.33.237.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 199.33.238.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 199.33.239.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 199.33.24.0/23 | 512 | ARIN | US | 22nd Oct 1993 |
| 199.33.241.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 199.33.242.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 199.33.246.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 199.33.247.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 199.33.249.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 199.33.250.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 199.33.251.0/24 | 256 | ARIN | US | 21st Jan 1994 |
| 199.33.252.0/24 | 256 | ARIN | US | 22nd Jan 1994 |
| 199.33.254.0/24 | 256 | ARIN | US | 22nd Jan 1994 |
| 199.33.255.0/24 | 256 | ARIN | US | 27th Oct 2015 |
| 199.33.66.0/23 | 512 | ARIN | US | 9th Jul 2015 |
| 199.33.81.0/24 | 256 | ARIN | US | 3rd Dec 1999 |
| 199.34.109.0/24 | 256 | ARIN | US | 23rd Sept 1996 |
| 199.34.124.0/24 | 256 | ARIN | US | 27th Oct 2008 |
| 199.34.128.0/18 | 16.4k | ARIN | US | 7th Jan 1994 |
| 199.34.192.0/19 | 8.2k | ARIN | US | 7th Jan 1994 |
| 199.34.224.0/22 | 1k | ARIN | US | 7th Jan 1994 |
| 199.34.243.0/24 | 256 | ARIN | US | 9th Jan 2023 |
| 199.35.0.0/19 | 8.2k | ARIN | US | 22nd Oct 1993 |
| 199.35.128.0/17 | 32.8k | ARIN | US | 22nd Oct 1993 |
| 199.35.32.0/20 | 4.1k | ARIN | US | 22nd Oct 1993 |