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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 unannounced space registered through ARIN, largest first.
Unannounced blocks in United States
26,295 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 208.91.0.0/22 | 1k | ARIN |  US | 22nd May 2008 |
| 208.91.168.0/21 | 2k | ARIN | US | 11th Jun 2008 |
| 208.91.40.0/22 | 1k | ARIN | US | 29th May 2008 |
| 208.91.90.0/24 | 256 | ARIN | US | 14th Oct 2015 |
| 208.91.91.0/24 | 256 | ARIN | US | 2nd Jun 2008 |
| 208.92.124.0/22 | 1k | ARIN | US | 2nd Jul 2008 |
| 208.92.180.0/22 | 1k | ARIN | US | 9th Jul 2008 |
| 208.92.200.0/22 | 1k | ARIN | US | 10th Jul 2008 |
| 208.92.204.0/22 | 1k | ARIN | US | 14th Jul 2008 |
| 208.92.32.0/22 | 1k | ARIN | US | 25th Jun 2008 |
| 208.93.162.0/24 | 256 | ARIN | US | 7th Jun 2018 |
| 208.93.208.0/22 | 1k | ARIN | US | 8th Aug 2008 |
| 208.93.36.0/22 | 1k | ARIN | US | 24th Jul 2008 |
| 208.94.120.0/21 | 2k | ARIN | US | 29th Aug 2008 |
| 208.94.156.0/22 | 1k | ARIN | US | 4th Sept 2008 |
| 208.94.192.0/22 | 1k | ARIN | US | 8th Sept 2008 |
| 208.94.211.0/24 | 256 | ARIN | US | 20th Nov 2025 |
| 208.94.215.0/24 | 256 | ARIN | US | 26th Jan 2026 |
| 208.94.24.0/22 | 1k | ARIN | US | 21st Aug 2008 |
| 208.95.208.0/21 | 2k | ARIN | US | 26th Sept 2008 |
| 208.95.32.0/22 | 1k | ARIN | US | 16th Sept 2008 |
| 208.95.40.0/21 | 2k | ARIN | US | 16th Sept 2008 |
| 208.96.184.0/22 | 1k | ARIN | US | 24th Jul 2019 |
| 208.99.24.0/22 | 1k | ARIN | US | 5th Oct 2021 |
| 208.99.32.0/22 | 1k | ARIN | US | 5th Oct 2021 |
| 208.99.4.0/22 | 1k | ARIN | US | 4th Oct 2021 |
| 208.99.44.0/24 | 256 | ARIN | US | 21st Oct 2021 |
| 208.99.50.0/24 | 256 | ARIN | US | 8th Oct 2021 |
| 208.99.55.0/24 | 256 | ARIN | US | 13th Oct 2021 |
| 208.99.60.0/24 | 256 | ARIN | US | 30th Nov 2021 |
| 208.99.61.0/24 | 256 | ARIN | US | 4th Oct 2021 |
| 209.102.0.0/17 | 32.8k | ARIN | US | 9th Jul 1997 |
| 209.103.64.0/18 | 16.4k | ARIN | US | 11th Jul 1997 |
| 209.107.128.0/21 | 2k | ARIN | US | 5th Mar 2019 |
| 209.107.136.0/22 | 1k | ARIN | US | 5th Mar 2019 |
| 209.107.204.0/24 | 256 | ARIN | US | 16th Apr 2009 |
| 209.109.128.0/17 | 32.8k | ARIN | US | 3rd Sept 2003 |
| 209.110.0.0/18 | 16.4k | ARIN | US | 3rd Sept 2003 |
| 209.110.128.0/17 | 32.8k | ARIN | US | 15th Jul 1997 |
| 209.110.96.0/19 | 8.2k | ARIN | US | 15th Jul 1997 |
| 209.113.0.0/17 | 32.8k | ARIN | US | 31st Jul 1997 |
| 209.120.0.0/17 | 32.8k | ARIN | US | 31st Jul 1997 |
| 209.127.201.0/24 | 256 | ARIN | US | 24th Apr 2020 |
| 209.127.205.0/24 | 256 | ARIN | US | 8th Jan 2020 |
| 209.127.206.0/24 | 256 | ARIN | US | 31st Jan 2020 |
| 209.127.213.0/24 | 256 | ARIN | US | 5th May 2020 |
| 209.131.116.0/23 | 512 | ARIN | US | 26th May 2026 |
| 209.131.127.0/24 | 256 | ARIN | US | 10th Sept 2025 |
| 209.135.137.0/24 | 256 | ARIN | US | 12th Jun 2026 |
| 209.135.138.0/23 | 512 | ARIN | US | 5th Sept 1997 |