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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 192.234.67.0/24 | 256 | ARIN |  US | 6th Oct 1992 |
| 192.234.7.0/24 | 256 | ARIN | US | 28th Sept 1992 |
| 192.234.70.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.234.71.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.234.72.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.234.73.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.234.74.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.234.75.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.234.76.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.234.77.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.234.78.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.234.8.0/24 | 256 | ARIN | US | 28th Sept 1992 |
| 192.234.9.0/24 | 256 | ARIN | US | 28th Sept 1992 |
| 192.234.92.0/24 | 256 | ARIN | US | 13th Oct 1992 |
| 192.234.94.0/24 | 256 | ARIN | US | 13th Oct 1992 |
| 192.234.95.0/24 | 256 | ARIN | US | 13th Oct 1992 |
| 192.234.96.0/24 | 256 | ARIN | US | 13th Oct 1992 |
| 192.234.97.0/24 | 256 | ARIN | US | 13th Oct 1992 |
| 192.234.98.0/24 | 256 | ARIN |  CA | 13th Oct 1992 |
| 192.236.1.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.236.8.0/24 | 256 | ARIN | US | 6th Oct 1992 |
| 192.238.1.0/24 | 256 | RIPE NCC |  CH | 1st Sept 1993 |
| 192.238.10.0/24 | 256 | RIPE NCC | CH | 1st Sept 1993 |
| 192.238.16.0/24 | 256 | ARIN | US | 22nd May 2025 |
| 192.238.2.0/23 | 512 | RIPE NCC | CH | 1st Sept 1993 |
| 192.238.4.0/22 | 1k | RIPE NCC | CH | 1st Sept 1993 |
| 192.238.8.0/23 | 512 | RIPE NCC | CH | 1st Sept 1993 |
| 192.239.0.0/16 | 65.5k | ARIN | US | 15th Oct 1992 |
| 192.241.24.0/21 | 2k | ARIN | US | 28th Oct 1992 |
| 192.242.0.0/16 | 65.5k | ARIN | US | 23rd Oct 2018 |
| 192.243.0.0/20 | 4.1k | ARIN | US | 20th Oct 1992 |
| 192.243.192.0/20 | 4.1k | ARIN | US | 10th Nov 1992 |
| 192.243.208.0/22 | 1k | ARIN | US | 10th Nov 1992 |
| 192.243.212.0/24 | 256 | ARIN | US | 10th Nov 1992 |
| 192.243.38.0/24 | 256 | ARIN | US | 27th Oct 1992 |
| 192.245.100.0/24 | 256 | ARIN | US | 2nd Nov 1992 |
| 192.245.101.0/24 | 256 | ARIN | US | 2nd Nov 1992 |
| 192.245.103.0/24 | 256 | ARIN | US | 2nd Nov 1992 |
| 192.245.104.0/24 | 256 | ARIN | US | 2nd Nov 1992 |
| 192.245.106.0/23 | 512 | APNIC |  AU | 2nd Nov 1992 |
| 192.245.11.0/24 | 256 | APNIC |  ID | 27th Jan 2026 |
| 192.245.116.0/24 | 256 | ARIN | US | 4th Nov 1992 |
| 192.245.117.0/24 | 256 | ARIN | US | 4th Nov 1992 |
| 192.245.119.0/24 | 256 | ARIN | US | 4th Nov 1992 |
| 192.245.120.0/24 | 256 | ARIN | US | 4th Nov 1992 |
| 192.245.122.0/23 | 512 | ARIN | US | 4th Nov 1992 |
| 192.245.124.0/23 | 512 | ARIN | US | 4th Nov 1992 |
| 192.245.126.0/23 | 512 | ARIN | US | 4th Nov 1992 |
| 192.245.128.0/22 | 1k | ARIN | US | 4th Nov 1992 |
| 192.245.132.0/24 | 256 | ARIN | US | 4th Nov 1992 |