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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
Browse by country
Countries with the most unannounced blocks, largest first.
Unannounced blocks in United States
27,019 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 206.197.68.0/24 | 256 | ARIN |  US | 6th Jul 1995 |
| 206.197.70.0/24 | 256 | ARIN | US | 6th Jul 1995 |
| 206.197.71.0/24 | 256 | ARIN | US | 6th Jul 1995 |
| 206.197.72.0/24 | 256 | ARIN | US | 10th Jul 1995 |
| 206.197.73.0/24 | 256 | ARIN | US | 6th Jul 1995 |
| 206.197.75.0/24 | 256 | ARIN | US | 6th Jul 1995 |
| 206.197.77.0/24 | 256 | ARIN | US | 6th Jul 1995 |
| 206.197.78.0/24 | 256 | ARIN | US | 10th Jul 1995 |
| 206.197.79.0/24 | 256 | ARIN | US | 10th Jul 1995 |
| 206.197.8.0/24 | 256 | ARIN | US | 15th Jun 1995 |
| 206.197.80.0/24 | 256 | ARIN | US | 10th Jul 1995 |
| 206.197.81.0/24 | 256 | ARIN | US | 12th Jul 1995 |
| 206.197.82.0/24 | 256 | ARIN | US | 12th Jul 1995 |
| 206.197.83.0/24 | 256 | ARIN | US | 12th Jul 1995 |
| 206.197.84.0/24 | 256 | ARIN | US | 13th Jul 1995 |
| 206.197.85.0/24 | 256 | ARIN | US | 14th Jul 1995 |
| 206.197.86.0/24 | 256 | ARIN | US | 14th Jul 1995 |
| 206.197.89.0/24 | 256 | ARIN | US | 18th Jul 1995 |
| 206.197.92.0/24 | 256 | ARIN | US | 18th Jul 1995 |
| 206.197.93.0/24 | 256 | ARIN | US | 18th Jul 1995 |
| 206.197.94.0/24 | 256 | ARIN | US | 18th Jul 1995 |
| 206.197.95.0/24 | 256 | ARIN | US | 19th Jul 1995 |
| 206.197.96.0/24 | 256 | ARIN | US | 19th Jul 1995 |
| 206.197.97.0/24 | 256 | ARIN | US | 19th Jul 1995 |
| 206.197.98.0/24 | 256 | ARIN | US | 19th Jul 1995 |
| 206.197.99.0/24 | 256 | ARIN | US | 19th Jul 1995 |
| 206.198.232.0/21 | 2k | ARIN | US | 10th Aug 2017 |
| 206.201.135.0/24 | 256 | ARIN | US | 2nd Aug 1995 |
| 206.201.96.0/20 | 4.1k | ARIN | US | 1st Aug 1995 |
| 206.203.192.0/18 | 16.4k | ARIN | US | 9th Aug 1995 |
| 206.206.16.0/20 | 4.1k | RIPE NCC | US | 19th Jul 1995 |
| 206.206.32.0/19 | 8.2k | ARIN | US | 19th Jul 1995 |
| 206.207.72.0/23 | 512 | ARIN | US | 19th Jul 1995 |
| 206.207.75.0/24 | 256 | ARIN | US | 24th Jul 2025 |
| 206.207.76.0/22 | 1k | ARIN | US | 24th Jul 2025 |
| 206.208.104.0/21 | 2k | ARIN | US | 12th Sept 1995 |
| 206.208.144.0/21 | 2k | ARIN | US | 22nd Sept 1995 |
| 206.208.152.0/21 | 2k | ARIN | US | 22nd Sept 1995 |
| 206.208.160.0/21 | 2k | ARIN | US | 10th Oct 1995 |
| 206.208.192.0/21 | 2k | ARIN | US | 7th Nov 1995 |
| 206.208.240.0/21 | 2k | ARIN | US | 5th Dec 1995 |
| 206.208.248.0/21 | 2k | ARIN | US | 5th Dec 1995 |
| 206.208.40.0/21 | 2k | ARIN | US | 17th Aug 1995 |
| 206.208.48.0/21 | 2k | ARIN | US | 18th Aug 1995 |
| 206.208.72.0/21 | 2k | ARIN | US | 1st Sept 1995 |
| 206.208.8.0/21 | 2k | ARIN | US | 14th Aug 1995 |
| 206.208.80.0/21 | 2k | ARIN | US | 5th Sept 1995 |
| 206.209.100.0/22 | 1k | ARIN | US | 12th Jun 2007 |
| 206.209.104.0/23 | 512 | ARIN | US | 12th Jun 2007 |
| 206.209.106.0/24 | 256 | ARIN | US | 12th Jun 2007 |