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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,124 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.12.127.0/24 | 256 | ARIN |  US | 3rd Oct 1985 |
| 192.12.129.0/24 | 256 | ARIN |  CA | 21st Oct 1985 |
| 192.12.130.0/24 | 256 | ARIN | US | 30th Apr 1990 |
| 192.12.132.0/24 | 256 | ARIN | US | 15th Oct 1985 |
| 192.12.138.0/24 | 256 | ARIN | US | 15th Oct 1985 |
| 192.12.140.0/24 | 256 | ARIN | US | 15th Oct 1985 |
| 192.12.141.0/24 | 256 | ARIN | US | 23rd Oct 1985 |
| 192.12.142.0/24 | 256 | ARIN | US | 30th Oct 1985 |
| 192.12.143.0/24 | 256 | ARIN | US | 30th Oct 1985 |
| 192.12.145.0/24 | 256 | ARIN | US | 5th Nov 1985 |
| 192.12.150.0/23 | 512 | ARIN | US | 5th Nov 1985 |
| 192.12.152.0/23 | 512 | ARIN | US | 5th Nov 1985 |
| 192.12.154.0/24 | 256 | ARIN | US | 2nd Oct 2017 |
| 192.12.188.0/24 | 256 | ARIN | US | 13th Jan 1986 |
| 192.12.195.0/24 | 256 | ARIN | US | 13th Jan 1986 |
| 192.12.196.0/24 | 256 | ARIN | US | 16th May 1988 |
| 192.12.20.0/23 | 512 | ARIN | US | 21st May 2014 |
| 192.12.210.0/24 | 256 | ARIN | US | 18th Dec 1987 |
| 192.12.211.0/24 | 256 | ARIN | US | 19th Feb 1986 |
| 192.12.212.0/24 | 256 | ARIN | US | 20th Feb 1986 |
| 192.12.213.0/24 | 256 | ARIN | US | 20th Feb 1986 |
| 192.12.214.0/24 | 256 | ARIN | US | 2nd May 1990 |
| 192.12.215.0/24 | 256 | ARIN | CA | 2nd May 1990 |
| 192.12.216.0/24 | 256 | ARIN | US | 27th Feb 1986 |
| 192.12.217.0/24 | 256 | RIPE NCC |  CH | 9th Jun 1988 |
| 192.12.218.0/24 | 256 | RIPE NCC | CH | 9th Jun 1988 |
| 192.12.225.0/24 | 256 | ARIN | US | 30th Apr 1990 |
| 192.12.226.0/23 | 512 | ARIN | US | 30th Apr 1990 |
| 192.12.228.0/24 | 256 | ARIN | US | 30th Apr 1990 |
| 192.12.229.0/24 | 256 | ARIN | US | 2nd May 1990 |
| 192.12.23.0/24 | 256 | ARIN | US | 7th Mar 2014 |
| 192.12.230.0/24 | 256 | ARIN | US | 4th May 1990 |
| 192.12.231.0/24 | 256 | RIPE NCC |  GB | 14th May 1990 |
| 192.12.233.0/24 | 256 | ARIN | US | 14th May 1990 |
| 192.12.237.0/24 | 256 | ARIN | US | 5th Mar 1986 |
| 192.12.239.0/24 | 256 | ARIN | US | 11th Mar 1986 |
| 192.12.24.0/24 | 256 | ARIN | US | 8th Oct 1984 |
| 192.12.243.0/24 | 256 | ARIN | US | 11th Mar 1986 |
| 192.12.246.0/24 | 256 | ARIN | US | 11th Mar 1986 |
| 192.12.248.0/24 | 256 | ARIN | US | 18th Dec 1987 |
| 192.12.249.0/24 | 256 | ARIN | US | 18th Dec 1987 |
| 192.12.25.0/24 | 256 | ARIN | US | 8th Oct 1984 |
| 192.12.251.0/24 | 256 | ARIN | US | 18th Jan 1988 |
| 192.12.252.0/24 | 256 | ARIN | US | 14th Mar 1986 |
| 192.12.253.0/24 | 256 | ARIN | US | 14th Mar 1986 |
| 192.12.254.0/24 | 256 | ARIN | US | 14th Mar 1986 |
| 192.12.255.0/24 | 256 | ARIN | US | 14th Mar 1986 |
| 192.12.27.0/24 | 256 | ARIN | US | 18th Oct 1984 |
| 192.12.3.0/24 | 256 | ARIN | US | 11th Jun 1984 |
| 192.12.36.0/22 | 1k | ARIN | US | 9th Jan 1985 |