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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
26,971 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 140.170.0.0/16 | 65.5k | ARIN |  US | 8th May 1990 |
| 140.173.0.0/16 | 65.5k | ARIN | US | 16th May 1990 |
| 140.176.0.0/16 | 65.5k | ARIN | US | 16th May 1990 |
| 140.184.128.0/17 | 32.8k | ARIN | US | 14th Oct 2026 |
| 140.184.16.0/21 | 2k | APNIC | US | 16th May 1990 |
| 140.184.24.0/22 | 1k | ARIN | US | 14th Oct 2026 |
| 140.184.28.0/22 | 1k | RIPE NCC | US | 16th May 1990 |
| 140.184.64.0/19 | 8.2k | ARIN | US | 14th Oct 2026 |
| 140.184.8.0/21 | 2k | RIPE NCC | US | 16th May 1990 |
| 140.184.96.0/19 | 8.2k | RIPE NCC | US | 16th May 1990 |
| 140.190.112.0/21 | 2k | ARIN | US | 23rd Nov 2022 |
| 140.190.128.0/18 | 16.4k | ARIN | US | 23rd Nov 2022 |
| 140.190.192.0/19 | 8.2k | ARIN | US | 23rd Nov 2022 |
| 140.190.224.0/20 | 4.1k | ARIN | US | 23rd Nov 2022 |
| 140.190.240.0/21 | 2k | ARIN | US | 23rd Nov 2022 |
| 140.190.64.0/19 | 8.2k | ARIN | US | 23rd Nov 2022 |
| 140.190.96.0/20 | 4.1k | ARIN | US | 23rd Nov 2022 |
| 140.208.224.0/20 | 4.1k | ARIN | US | 11th Jun 1990 |
| 140.222.0.0/16 | 65.5k | ARIN | US | 15th Jun 1990 |
| 140.232.128.0/20 | 4.1k | ARIN | US | 21st May 1990 |
| 140.232.144.0/21 | 2k | ARIN | US | 21st May 1990 |
| 140.232.152.0/22 | 1k | ARIN | US | 21st May 1990 |
| 140.232.156.0/24 | 256 | ARIN | US | 3rd Nov 2026 |
| 140.232.157.0/24 | 256 | ARIN | US | 21st May 1990 |
| 140.232.158.0/24 | 256 | ARIN | US | 21st May 1990 |
| 140.232.159.0/24 | 256 | ARIN | US | 4th Nov 2026 |
| 140.232.160.0/22 | 1k | ARIN | US | 21st May 2026 |
| 140.232.164.0/22 | 1k | ARIN | US | 21st May 1990 |
| 140.232.168.0/21 | 2k | ARIN | US | 21st May 1990 |
| 140.232.176.0/21 | 2k | ARIN | US | 21st May 1990 |
| 140.232.66.0/23 | 512 | ARIN | US | 21st May 1990 |
| 140.232.68.0/22 | 1k | ARIN | US | 21st May 1990 |
| 140.232.72.0/23 | 512 | ARIN | US | 21st May 1990 |
| 140.232.74.0/23 | 512 | ARIN | US | 14th Oct 2026 |
| 140.232.78.0/23 | 512 | ARIN | US | 21st May 1990 |
| 140.232.84.0/22 | 1k | ARIN | US | 21st May 1990 |
| 140.232.88.0/24 | 256 | ARIN | US | 15th May 2026 |
| 140.232.93.0/24 | 256 | ARIN | US | 21st May 1990 |
| 140.232.94.0/23 | 512 | ARIN | US | 21st May 1990 |
| 140.232.96.0/19 | 8.2k | ARIN | US | 21st May 1990 |
| 140.235.112.0/23 | 512 | ARIN | US | 3rd Oct 2024 |
| 140.235.114.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.120.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.126.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.127.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.152.0/22 | 1k | ARIN | US | 3rd Oct 2024 |
| 140.235.185.0/24 | 256 | ARIN | US | 9th Oct 2024 |
| 140.235.215.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.238.0/24 | 256 | ARIN | US | 3rd Oct 2024 |
| 140.235.244.0/22 | 1k | ARIN | US | 3rd Oct 2024 |