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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 199.248.16.0/21 | 2k | ARIN |  US | 3rd May 1994 |
| 199.248.160.0/23 | 512 | ARIN | US | 15th Sept 1994 |
| 199.248.162.0/24 | 256 | ARIN | US | 15th Sept 1994 |
| 199.248.163.0/24 | 256 | ARIN | US | 15th Sept 1994 |
| 199.248.169.0/24 | 256 | ARIN | US | 16th Sept 1994 |
| 199.248.170.0/24 | 256 | ARIN | US | 16th Sept 1994 |
| 199.248.171.0/24 | 256 | ARIN | US | 16th Sept 1994 |
| 199.248.172.0/24 | 256 | ARIN | US | 16th Sept 1994 |
| 199.248.179.0/24 | 256 | ARIN | US | 19th Sept 1994 |
| 199.248.180.0/24 | 256 | ARIN | US | 19th Sept 1994 |
| 199.248.181.0/24 | 256 | ARIN | US | 19th Sept 1994 |
| 199.248.182.0/24 | 256 | ARIN | US | 20th Sept 1994 |
| 199.248.184.0/24 | 256 | ARIN | US | 20th Sept 1994 |
| 199.248.187.0/24 | 256 | ARIN | US | 21st Sept 1994 |
| 199.248.188.0/24 | 256 | ARIN | US | 21st Sept 1994 |
| 199.248.190.0/24 | 256 | ARIN | US | 21st Sept 1994 |
| 199.248.191.0/24 | 256 | ARIN | US | 22nd Sept 1994 |
| 199.248.192.0/24 | 256 | ARIN | US | 22nd Sept 1994 |
| 199.248.193.0/24 | 256 | ARIN | US | 22nd Sept 1994 |
| 199.248.194.0/24 | 256 | ARIN | US | 22nd Sept 1994 |
| 199.248.195.0/24 | 256 | ARIN | US | 22nd Sept 1994 |
| 199.248.196.0/24 | 256 | ARIN | US | 23rd Sept 1994 |
| 199.248.199.0/24 | 256 | ARIN | US | 16th Mar 2012 |
| 199.248.202.0/24 | 256 | ARIN | US | 23rd Sept 1994 |
| 199.248.203.0/24 | 256 | ARIN | US | 23rd Sept 1994 |
| 199.248.204.0/24 | 256 | ARIN | US | 23rd Sept 1994 |
| 199.248.206.0/24 | 256 | ARIN | US | 27th Sept 1994 |
| 199.248.207.0/24 | 256 | ARIN | US | 27th Sept 1994 |
| 199.248.210.0/24 | 256 | ARIN | US | 28th Sept 1994 |
| 199.248.212.0/24 | 256 | ARIN | US | 30th Sept 1994 |
| 199.248.213.0/24 | 256 | ARIN | US | 30th Sept 1994 |
| 199.248.214.0/24 | 256 | ARIN | US | 30th Sept 1994 |
| 199.248.215.0/24 | 256 | ARIN | US | 30th Sept 1994 |
| 199.248.216.0/24 | 256 | ARIN | US | 26th Jun 2024 |
| 199.248.217.0/24 | 256 | ARIN | US | 3rd Oct 1994 |
| 199.248.218.0/24 | 256 | ARIN | US | 3rd Oct 1994 |
| 199.248.219.0/24 | 256 | ARIN | US | 3rd Oct 1994 |
| 199.248.220.0/24 | 256 | ARIN | US | 6th Oct 2025 |
| 199.248.221.0/24 | 256 | ARIN | US | 4th Oct 1994 |
| 199.248.222.0/24 | 256 | ARIN | US | 4th Oct 1994 |
| 199.248.223.0/24 | 256 | ARIN | US | 4th Oct 1994 |
| 199.248.224.0/24 | 256 | ARIN | US | 4th Oct 1994 |
| 199.248.227.0/24 | 256 | ARIN | US | 5th Oct 1994 |
| 199.248.228.0/24 | 256 | ARIN | US | 5th Oct 1994 |
| 199.248.229.0/24 | 256 | ARIN | US | 5th Oct 1994 |
| 199.248.231.0/24 | 256 | ARIN | US | 5th Oct 1994 |
| 199.248.234.0/24 | 256 | ARIN | US | 5th Oct 1994 |
| 199.248.235.0/24 | 256 | ARIN | US | 5th Oct 1994 |
| 199.248.237.0/24 | 256 | ARIN | US | 5th Oct 1994 |
| 199.248.238.0/24 | 256 | ARIN | US | 5th Oct 1994 |