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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,195 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.73.78.0/24 | 256 | ARIN |  US | 5th Aug 1990 |
| 192.73.79.0/24 | 256 | ARIN | US | 5th Aug 1990 |
| 192.73.8.0/24 | 256 | ARIN | US | 3rd Jul 1990 |
| 192.73.9.0/24 | 256 | ARIN | US | 3rd Jul 1990 |
| 192.74.138.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.74.213.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.74.218.0/23 | 512 | ARIN | US | 26th Mar 1990 |
| 192.75.1.0/24 | 256 | ARIN |  CA | 8th Aug 1990 |
| 192.75.100.0/24 | 256 | ARIN | CA | 27th Apr 1993 |
| 192.75.102.0/23 | 512 | ARIN | CA | 26th Mar 1990 |
| 192.75.104.0/24 | 256 | ARIN | CA | 11th Jul 1991 |
| 192.75.107.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.108.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.109.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.110.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.111.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.112.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.113.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.115.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.119.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.124.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.125.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.126.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.127.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.128.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.129.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.13.0/24 | 256 | ARIN | CA | 26th Mar 1990 |
| 192.75.130.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.132.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.133.0/24 | 256 | ARIN | CA | 5th Feb 1992 |
| 192.75.137.0/24 | 256 | APNIC |  HK | 4th Mar 2019 |
| 192.75.141.0/24 | 256 | ARIN | CA | 26th Mar 1990 |
| 192.75.142.0/24 | 256 | ARIN | CA | 6th Jul 1993 |
| 192.75.143.0/24 | 256 | ARIN | CA | 26th Mar 1990 |
| 192.75.145.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.75.146.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.75.148.0/24 | 256 | ARIN | CA | 14th Jun 1991 |
| 192.75.149.0/24 | 256 | ARIN | CA | 14th Jun 1991 |
| 192.75.15.0/24 | 256 | ARIN | CA | 21st Sept 1990 |
| 192.75.150.0/24 | 256 | ARIN | CA | 14th Jun 1991 |
| 192.75.151.0/24 | 256 | ARIN | CA | 21st Jun 1991 |
| 192.75.152.0/24 | 256 | ARIN | CA | 21st Jun 1991 |
| 192.75.153.0/24 | 256 | ARIN | CA | 28th Jun 1991 |
| 192.75.154.0/24 | 256 | ARIN | CA | 26th Mar 1990 |
| 192.75.155.0/24 | 256 | ARIN | CA | 26th Mar 1990 |
| 192.75.156.0/24 | 256 | ARIN | CA | 11th Jul 1991 |
| 192.75.157.0/24 | 256 | ARIN | CA | 16th Jul 1991 |
| 192.75.159.0/24 | 256 | ARIN | CA | 20th Jul 1993 |
| 192.75.16.0/24 | 256 | ARIN | CA | 21st Sept 1990 |
| 192.75.160.0/24 | 256 | ARIN | CA | 26th Mar 1990 |