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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 192.73.19.0/24 | 256 | RIPE NCC |  GB | 5th Jul 1990 |
| 192.73.2.0/24 | 256 | ARIN |  US | 29th Jun 1990 |
| 192.73.20.0/24 | 256 | RIPE NCC | GB | 5th Jul 1990 |
| 192.73.205.0/24 | 256 | ARIN | US | 5th Aug 1990 |
| 192.73.217.0/24 | 256 | ARIN | US | 14th Aug 1990 |
| 192.73.218.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.73.219.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.73.221.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.73.225.0/24 | 256 | ARIN | US | 28th Aug 1990 |
| 192.73.226.0/24 | 256 | RIPE NCC |  BE | 28th Aug 1990 |
| 192.73.227.0/24 | 256 | ARIN | US | 28th Aug 1990 |
| 192.73.228.0/24 | 256 | ARIN | US | 28th Aug 1990 |
| 192.73.229.0/24 | 256 | RIPE NCC | GB | 28th Aug 1990 |
| 192.73.230.0/24 | 256 | ARIN | US | 28th Aug 1990 |
| 192.73.231.0/24 | 256 | ARIN | US | 28th Aug 1990 |
| 192.73.3.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.73.30.0/24 | 256 | ARIN | US | 12th Jul 1990 |
| 192.73.32.0/24 | 256 | ARIN | US | 12th Jul 1990 |
| 192.73.35.0/24 | 256 | RIPE NCC |  CH | 18th May 1990 |
| 192.73.36.0/22 | 1k | RIPE NCC | CH | 18th May 1990 |
| 192.73.4.0/24 | 256 | ARIN | US | 3rd Jul 1990 |
| 192.73.40.0/22 | 1k | RIPE NCC | CH | 18th May 1990 |
| 192.73.44.0/24 | 256 | RIPE NCC | CH | 18th May 1990 |
| 192.73.46.0/24 | 256 | ARIN | US | 18th Jul 1990 |
| 192.73.47.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.73.49.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.73.5.0/24 | 256 | ARIN |  CA | 3rd Jul 1990 |
| 192.73.50.0/24 | 256 | ARIN | US | 12th Nov 1996 |
| 192.73.51.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.52.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.55.0/24 | 256 | ARIN | US | 26th Jul 1990 |
| 192.73.57.0/24 | 256 | ARIN | US | 30th Jul 1990 |
| 192.73.58.0/24 | 256 | ARIN | US | 30th Jul 1990 |
| 192.73.59.0/24 | 256 | ARIN | US | 30th Jul 1990 |
| 192.73.6.0/24 | 256 | ARIN | US | 3rd Jul 1990 |
| 192.73.60.0/24 | 256 | ARIN | US | 30th Jul 1990 |
| 192.73.61.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.63.0/24 | 256 | ARIN | US | 26th Mar 1990 |
| 192.73.64.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.65.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.66.0/24 | 256 | APNIC |  AU | 23rd Jul 1990 |
| 192.73.68.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.69.0/24 | 256 | ARIN | US | 5th Dec 2014 |
| 192.73.70.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.71.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.72.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.73.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.74.0/24 | 256 | ARIN | US | 31st Jul 1990 |
| 192.73.75.0/24 | 256 | ARIN | US | 2nd Aug 1990 |
| 192.73.77.0/24 | 256 | ARIN | US | 3rd Aug 1990 |