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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 in Australia
2,391 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 203.16.173.0/24 | 256 | APNIC |  AU | 12th Jun 1995 |
| 203.16.176.0/24 | 256 | APNIC | AU | 12th Jun 1995 |
| 203.16.197.0/24 | 256 | APNIC | AU | 13th Jun 1995 |
| 203.16.198.0/24 | 256 | APNIC | AU | 13th Jun 1995 |
| 203.16.204.0/24 | 256 | APNIC | AU | 14th Jun 1995 |
| 203.16.243.0/24 | 256 | APNIC | AU | 20th Jun 1995 |
| 203.161.182.0/24 | 256 | APNIC | AU | 24th Aug 2009 |
| 203.161.186.0/24 | 256 | APNIC | AU | 27th Aug 2009 |
| 203.167.24.0/22 | 1k | APNIC | AU | 25th Nov 2015 |
| 203.17.10.0/24 | 256 | APNIC | AU | 22nd Jun 1995 |
| 203.17.122.0/24 | 256 | APNIC | AU | 14th Jul 1995 |
| 203.17.140.0/22 | 1k | APNIC | AU | 14th Jul 1995 |
| 203.17.144.0/22 | 1k | APNIC | AU | 14th Jul 1995 |
| 203.17.153.0/24 | 256 | APNIC | AU | 15th Jul 1995 |
| 203.17.16.0/23 | 512 | APNIC | AU | 22nd Jun 1995 |
| 203.17.184.0/24 | 256 | APNIC | AU | 26th Jul 1995 |
| 203.17.196.0/22 | 1k | APNIC | AU | 26th Jul 1995 |
| 203.17.20.0/24 | 256 | APNIC | AU | 22nd Jun 1995 |
| 203.17.230.0/24 | 256 | APNIC | AU | 27th Jul 1995 |
| 203.17.239.0/24 | 256 | APNIC | AU | 31st Jul 1995 |
| 203.17.246.0/24 | 256 | APNIC | AU | 31st Jul 1995 |
| 203.17.252.0/24 | 256 | APNIC | AU | 31st Jul 1995 |
| 203.17.254.0/24 | 256 | APNIC | AU | 31st Jul 1995 |
| 203.17.26.0/23 | 512 | APNIC | AU | 5th Jul 1995 |
| 203.17.72.0/24 | 256 | APNIC | AU | 12th Jul 1995 |
| 203.17.96.0/21 | 2k | APNIC | AU | 14th Jul 1995 |
| 203.170.92.0/22 | 1k | APNIC | AU | 4th Apr 2008 |
| 203.175.112.0/21 | 2k | APNIC | AU | 28th Apr 2006 |
| 203.176.189.0/24 | 256 | APNIC | AU | 24th Apr 2008 |
| 203.18.14.0/23 | 512 | APNIC | AU | 16th Apr 2007 |
| 203.18.154.0/24 | 256 | APNIC | AU | 15th Aug 1995 |
| 203.18.155.0/24 | 256 | APNIC | AU | 16th Aug 1995 |
| 203.18.160.0/24 | 256 | APNIC | AU | 16th Aug 1995 |
| 203.18.164.0/22 | 1k | APNIC | AU | 16th Aug 1995 |
| 203.18.186.0/23 | 512 | APNIC | AU | 16th Aug 1995 |
| 203.18.188.0/22 | 1k | APNIC | AU | 16th Apr 2010 |
| 203.18.19.0/24 | 256 | APNIC | AU | 2nd Aug 1995 |
| 203.18.196.0/24 | 256 | APNIC | AU | 17th Aug 1995 |
| 203.18.204.0/22 | 1k | APNIC | AU | 17th Aug 1995 |
| 203.18.209.0/24 | 256 | APNIC | AU | 17th Aug 1995 |
| 203.18.22.0/24 | 256 | APNIC | AU | 2nd Aug 1995 |
| 203.18.224.0/22 | 1k | APNIC | AU | 18th Aug 1995 |
| 203.18.231.0/24 | 256 | APNIC | AU | 18th Aug 1995 |
| 203.18.236.0/22 | 1k | APNIC | AU | 18th Aug 1995 |
| 203.18.244.0/24 | 256 | APNIC | AU | 18th Aug 1995 |
| 203.18.28.0/24 | 256 | APNIC | AU | 2nd Aug 1995 |
| 203.18.32.0/24 | 256 | APNIC | AU | 2nd Aug 1995 |
| 203.18.56.0/24 | 256 | APNIC | AU | 3rd Aug 1995 |
| 203.18.58.0/24 | 256 | APNIC | AU | 4th Aug 1995 |
| 203.18.64.0/21 | 2k | APNIC | AU | 4th Aug 1995 |