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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
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Countries with the most unannounced blocks, largest first.
Unannounced blocks
85,195 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.6.74.0/24 | 256 | ARIN |  US | 26th Aug 1983 |
| 192.6.75.0/24 | 256 | ARIN | US | 26th Aug 1983 |
| 192.6.78.0/24 | 256 | ARIN | US | 26th Aug 1983 |
| 192.6.79.0/24 | 256 | ARIN | US | 26th Aug 1983 |
| 192.6.8.0/24 | 256 | ARIN | US | 26th Aug 1983 |
| 192.6.80.0/23 | 512 | ARIN | US | 26th Aug 1983 |
| 192.6.84.0/23 | 512 | ARIN | US | 26th Aug 1983 |
| 192.6.86.0/24 | 256 | ARIN | US | 26th Aug 1983 |
| 192.6.88.0/23 | 512 | ARIN | US | 26th Aug 1983 |
| 192.6.96.0/23 | 512 | ARIN | US | 26th Aug 1983 |
| 192.6.98.0/24 | 256 | ARIN | US | 26th Aug 1983 |
| 192.6.99.0/24 | 256 | ARIN | US | 26th Aug 1983 |
| 192.64.0.0/24 | 256 | ARIN | US | 10th Oct 2014 |
| 192.64.100.0/24 | 256 | RIPE NCC |  BE | 14th Oct 1993 |
| 192.64.101.0/24 | 256 | RIPE NCC | BE | 14th Oct 1993 |
| 192.64.102.0/24 | 256 | RIPE NCC | BE | 14th Oct 1993 |
| 192.64.103.0/24 | 256 | RIPE NCC | BE | 14th Oct 1993 |
| 192.64.104.0/21 | 2k | ARIN | US | 14th Dec 2012 |
| 192.64.125.0/24 | 256 | RIPE NCC |  GB | 12th Nov 2019 |
| 192.64.16.0/23 | 512 | ARIN | US | 19th Apr 1994 |
| 192.64.160.0/24 | 256 | ARIN | US | 5th Dec 2014 |
| 192.64.161.0/24 | 256 | ARIN |  CA | 3rd Oct 1989 |
| 192.64.164.0/24 | 256 | ARIN | CA | 3rd Oct 1989 |
| 192.64.166.0/23 | 512 | ARIN | US | 31st Oct 2014 |
| 192.64.198.0/24 | 256 | ARIN | US | 19th Apr 1994 |
| 192.64.202.0/24 | 256 | RIPE NCC |  DE | 1st Jan 1984 |
| 192.64.224.0/23 | 512 | ARIN | US | 17th Nov 2014 |
| 192.64.24.0/24 | 256 | ARIN | US | 19th Mar 2026 |
| 192.64.25.0/24 | 256 | ARIN | US | 27th Mar 2026 |
| 192.64.28.0/24 | 256 | RIPE NCC |  AT | 13th Jan 1994 |
| 192.64.29.0/24 | 256 | ARIN | US | 6th Jul 2020 |
| 192.64.38.0/24 | 256 | ARIN | CA | 7th Jun 1995 |
| 192.64.4.0/22 | 1k | ARIN | US | 5th Dec 2012 |
| 192.64.46.0/23 | 512 | ARIN | US | 14th Jun 2001 |
| 192.64.48.0/22 | 1k | ARIN | US | 14th Jun 2001 |
| 192.64.68.0/24 | 256 | ARIN | US | 3rd Oct 1989 |
| 192.64.69.0/24 | 256 | ARIN | US | 13th Nov 1990 |
| 192.64.88.0/24 | 256 | ARIN | US | 17th Sept 1993 |
| 192.64.89.0/24 | 256 | ARIN | US | 29th Sept 2014 |
| 192.64.96.0/24 | 256 | ARIN | US | 3rd Oct 1989 |
| 192.64.98.0/23 | 512 | ARIN | US | 21st Oct 2014 |
| 192.65.100.0/22 | 1k | ARIN | US | 13th Nov 1989 |
| 192.65.104.0/21 | 2k | ARIN | US | 13th Nov 1989 |
| 192.65.112.0/20 | 4.1k | ARIN | US | 13th Nov 1989 |
| 192.65.128.0/24 | 256 | ARIN | US | 13th Nov 1989 |
| 192.65.129.0/24 | 256 | ARIN | US | 13th Nov 1989 |
| 192.65.132.0/24 | 256 | RIPE NCC | GB | 14th Nov 1989 |
| 192.65.135.0/24 | 256 | ARIN | US | 14th Nov 1989 |
| 192.65.136.0/24 | 256 | ARIN | US | 15th Nov 1989 |
| 192.65.137.0/24 | 256 | ARIN | US | 16th Nov 1989 |