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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,201 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.231.55.0/24 | 256 | ARIN |  US | 25th Sept 1992 |
| 192.231.57.0/24 | 256 | ARIN | US | 25th Sept 1992 |
| 192.231.58.0/24 | 256 | ARIN | US | 25th Sept 1992 |
| 192.231.6.0/24 | 256 | ARIN | US | 22nd Sept 1992 |
| 192.231.60.0/24 | 256 | ARIN | US | 25th Sept 1992 |
| 192.231.61.0/24 | 256 | ARIN | US | 25th Sept 1992 |
| 192.231.62.0/24 | 256 | ARIN | US | 25th Sept 1992 |
| 192.231.64.0/24 | 256 | ARIN | US | 25th Sept 1992 |
| 192.231.65.0/24 | 256 | ARIN | US | 6th Aug 2015 |
| 192.231.66.0/24 | 256 | ARIN |  CA | 30th Sept 1992 |
| 192.231.67.0/24 | 256 | RIPE NCC |  AT | 30th Sept 1992 |
| 192.231.69.0/24 | 256 | ARIN | US | 30th Sept 1992 |
| 192.231.7.0/24 | 256 | ARIN | US | 22nd Sept 1992 |
| 192.231.70.0/24 | 256 | ARIN | US | 30th Sept 1992 |
| 192.231.73.0/24 | 256 | ARIN | US | 30th Sept 1992 |
| 192.231.74.0/24 | 256 | ARIN | US | 30th Sept 1992 |
| 192.231.75.0/24 | 256 | ARIN | US | 30th Sept 1992 |
| 192.231.76.0/24 | 256 | ARIN | US | 30th Sept 1992 |
| 192.231.81.0/24 | 256 | ARIN | US | 1st Oct 1992 |
| 192.231.82.0/24 | 256 | RIPE NCC |  DE | 1st Oct 1992 |
| 192.231.87.0/24 | 256 | ARIN | US | 1st Oct 1992 |
| 192.231.88.0/24 | 256 | ARIN | US | 1st Oct 1992 |
| 192.231.9.0/24 | 256 | ARIN | US | 22nd Sept 1992 |
| 192.231.90.0/24 | 256 | ARIN | US | 1st Oct 1992 |
| 192.231.93.0/24 | 256 | ARIN |  PR | 1st Oct 1992 |
| 192.231.94.0/23 | 512 | ARIN | PR | 1st Oct 1992 |
| 192.231.96.0/23 | 512 | ARIN | PR | 1st Oct 1992 |
| 192.231.98.0/23 | 512 | ARIN | US | 1st Oct 1992 |
| 192.232.1.0/24 | 256 | ARIN | US | 21st Sept 1992 |
| 192.232.10.0/24 | 256 | ARIN | US | 21st Sept 1992 |
| 192.232.2.0/23 | 512 | ARIN | US | 21st Sept 1992 |
| 192.232.34.0/23 | 512 | APNIC |  CN | 4th Jan 2026 |
| 192.232.38.0/23 | 512 | APNIC |  ID | 5th Jan 2026 |
| 192.232.4.0/22 | 1k | ARIN | US | 21st Sept 1992 |
| 192.232.44.0/23 | 512 | APNIC | CN | 6th Jan 2026 |
| 192.232.46.0/23 | 512 | APNIC | CN | 6th Jan 2026 |
| 192.232.8.0/23 | 512 | ARIN | US | 21st Sept 1992 |
| 192.234.0.0/24 | 256 | ARIN | CA | 31st Jul 2015 |
| 192.234.10.0/23 | 512 | ARIN | US | 30th Sept 1992 |
| 192.234.100.0/24 | 256 | ARIN | US | 13th Oct 1992 |
| 192.234.102.0/24 | 256 | LACNIC |  MX | 29th Sept 2022 |
| 192.234.103.0/24 | 256 | ARIN | US | 13th Oct 1992 |
| 192.234.107.0/24 | 256 | ARIN | US | 19th Oct 1992 |
| 192.234.108.0/24 | 256 | ARIN | US | 19th Oct 1992 |
| 192.234.109.0/24 | 256 | ARIN | US | 19th Oct 1992 |
| 192.234.112.0/24 | 256 | ARIN | US | 19th Oct 1992 |
| 192.234.113.0/24 | 256 | ARIN | US | 5th Aug 2015 |
| 192.234.114.0/23 | 512 | ARIN | US | 19th Oct 1992 |
| 192.234.116.0/23 | 512 | ARIN | US | 19th Oct 1992 |
| 192.234.124.0/24 | 256 | ARIN | US | 16th Oct 1992 |