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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 203.55.120.0/23 | 512 | APNIC |  AU | 11th Dec 1996 |
| 203.55.130.0/24 | 256 | APNIC | AU | 13th Dec 1996 |
| 203.55.144.0/24 | 256 | APNIC | AU | 13th Dec 1996 |
| 203.55.156.0/24 | 256 | APNIC | AU | 13th Dec 1996 |
| 203.55.19.0/24 | 256 | APNIC | AU | 29th Nov 1996 |
| 203.55.216.0/23 | 512 | APNIC | AU | 14th Jan 1997 |
| 203.55.220.0/24 | 256 | APNIC | AU | 15th Jan 1997 |
| 203.55.226.0/24 | 256 | APNIC | AU | 15th Jan 1997 |
| 203.55.28.0/23 | 512 | APNIC | AU | 29th Nov 1996 |
| 203.55.39.0/24 | 256 | APNIC | AU | 29th Nov 1996 |
| 203.55.42.0/24 | 256 | APNIC | AU | 29th Nov 1996 |
| 203.55.45.0/24 | 256 | APNIC | AU | 3rd Dec 1996 |
| 203.55.48.0/23 | 512 | APNIC |  SG | 3rd Dec 1996 |
| 203.55.50.0/23 | 512 | APNIC | AU | 3rd Dec 1996 |
| 203.55.53.0/24 | 256 | APNIC | AU | 3rd Dec 1996 |
| 203.55.54.0/23 | 512 | APNIC | AU | 3rd Dec 1996 |
| 203.55.56.0/22 | 1k | APNIC | AU | 30th Nov 2006 |
| 203.55.65.0/24 | 256 | APNIC | AU | 3rd Dec 1996 |
| 203.55.67.0/24 | 256 | APNIC |  PH | 1st Jun 2007 |
| 203.55.68.0/24 | 256 | APNIC |  FJ | 15th Sept 2025 |
| 203.55.79.0/24 | 256 | APNIC | AU | 4th Dec 1996 |
| 203.55.92.0/24 | 256 | APNIC | AU | 5th Dec 1996 |
| 203.55.95.0/24 | 256 | APNIC | AU | 5th Dec 1996 |
| 203.56.122.0/24 | 256 | APNIC | AU | 17th Jan 1997 |
| 203.56.14.0/23 | 512 | APNIC |  MY | 15th Jan 1997 |
| 203.56.16.0/24 | 256 | APNIC | AU | 15th Jan 1997 |
| 203.56.162.0/23 | 512 | RIPE NCC |  SE | 20th Jan 1997 |
| 203.56.168.0/24 | 256 | APNIC | AU | 20th Jan 1997 |
| 203.56.170.0/24 | 256 | APNIC | AU | 20th Jan 1997 |
| 203.56.177.0/24 | 256 | APNIC | AU | 20th Jan 1997 |
| 203.56.19.0/24 | 256 | APNIC | AU | 15th Jan 1997 |
| 203.56.197.0/24 | 256 | APNIC | AU | 20th Jan 1997 |
| 203.56.213.0/24 | 256 | APNIC | AU | 23rd Jan 1997 |
| 203.56.215.0/24 | 256 | APNIC | AU | 23rd Jan 1997 |
| 203.56.217.0/24 | 256 | APNIC | AU | 23rd Jan 1997 |
| 203.56.220.0/22 | 1k | APNIC | AU | 23rd Jan 1997 |
| 203.56.227.0/24 | 256 | APNIC |  CN | 14th Apr 2011 |
| 203.56.231.0/24 | 256 | APNIC | CN | 9th Jun 2016 |
| 203.56.236.0/22 | 1k | APNIC | AU | 29th Jan 1997 |
| 203.56.250.0/24 | 256 | APNIC | AU | 29th Jan 1997 |
| 203.56.251.0/24 | 256 | APNIC |  HK | 29th Jan 1997 |
| 203.56.27.0/24 | 256 | APNIC | AU | 15th Jan 1997 |
| 203.56.32.0/23 | 512 | APNIC |  NZ | 15th Jan 1997 |
| 203.56.42.0/24 | 256 | APNIC | AU | 15th Jan 1997 |
| 203.56.44.0/24 | 256 | APNIC | AU | 15th Jan 1997 |
| 203.56.5.0/24 | 256 | APNIC | AU | 15th Jan 1997 |
| 203.56.56.0/22 | 1k | APNIC | AU | 15th Jan 1997 |
| 203.56.6.0/24 | 256 | APNIC | AU | 15th Jan 1997 |
| 203.56.62.0/23 | 512 | APNIC | AU | 16th Jan 1997 |
| 203.56.87.0/24 | 256 | APNIC | HK | 16th Jan 1997 |