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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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.
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Countries with the most unannounced blocks, largest first.
Unannounced blocks
85,493 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 203.56.97.0/24 | 256 | APNIC |  AU | 16th Jan 1997 |
| 203.56.98.0/24 | 256 | APNIC | AU | 16th Jan 1997 |
| 203.57.10.0/24 | 256 | APNIC | AU | 29th Jan 1997 |
| 203.57.113.0/24 | 256 | APNIC | AU | 4th Feb 1997 |
| 203.57.145.0/24 | 256 | APNIC |  NZ | 9th Nov 2005 |
| 203.57.152.0/22 | 1k | APNIC | AU | 6th Feb 1997 |
| 203.57.246.0/23 | 512 | APNIC |  CN | 14th Apr 2011 |
| 203.57.250.0/23 | 512 | APNIC | AU | 7th Feb 1997 |
| 203.57.253.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.57.3.0/24 | 256 | APNIC | AU | 29th Jan 1997 |
| 203.57.36.0/23 | 512 | APNIC | AU | 31st Jan 1997 |
| 203.57.76.0/24 | 256 | APNIC | AU | 3rd Feb 1997 |
| 203.57.91.0/24 | 256 | APNIC | AU | 3rd Feb 1997 |
| 203.6.130.0/24 | 256 | APNIC |  US | 11th Jul 1994 |
| 203.6.131.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.6.133.0/24 | 256 | APNIC | AU | 11th Jul 1994 |
| 203.6.134.0/24 | 256 | APNIC | AU | 11th Jul 1994 |
| 203.6.136.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.6.138.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.6.142.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.6.150.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.6.152.0/22 | 1k | APNIC | AU | 21st Jul 1994 |
| 203.6.157.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.6.159.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.6.192.0/20 | 4.1k | APNIC | AU | 20th Jul 1994 |
| 203.6.212.0/22 | 1k | APNIC | AU | 15th Nov 2018 |
| 203.6.245.0/24 | 256 | APNIC | AU | 28th Jul 1994 |
| 203.6.248.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.6.252.0/23 | 512 | APNIC | AU | 13th Apr 1994 |
| 203.6.255.0/24 | 256 | APNIC | AU | 5th Aug 1994 |
| 203.62.128.0/23 | 512 | APNIC | AU | 10th Feb 1997 |
| 203.62.143.0/24 | 256 | ARIN | US | 23rd Feb 2026 |
| 203.62.157.0/24 | 256 | APNIC | AU | 11th Feb 1997 |
| 203.62.160.0/24 | 256 | APNIC | AU | 11th Feb 1997 |
| 203.62.161.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.62.162.0/24 | 256 | APNIC | AU | 11th Feb 1997 |
| 203.62.164.0/24 | 256 | APNIC | AU | 11th Feb 1997 |
| 203.62.189.0/24 | 256 | APNIC | AU | 14th Feb 1997 |
| 203.62.195.0/24 | 256 | APNIC |  SG | 19th Jun 2007 |
| 203.62.197.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.62.198.0/24 | 256 | APNIC | AU | 14th Feb 1997 |
| 203.62.228.0/22 | 1k | APNIC | CN | 14th Apr 2011 |
| 203.62.232.0/23 | 512 | APNIC | AU | 21st Feb 1997 |
| 203.62.234.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.62.235.0/24 | 256 | APNIC | AU | 24th Feb 1997 |
| 203.62.246.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.7.129.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.7.132.0/22 | 1k | APNIC | AU | 5th Aug 1994 |
| 203.7.138.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.7.147.0/24 | 256 | APNIC | CN | 14th Apr 2011 |