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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,536 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 203.20.44.0/24 | 256 | APNIC |  CN | 9th Jun 2016 |
| 203.20.45.0/24 | 256 | APNIC |  AU | 22nd Sept 1995 |
| 203.20.48.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.20.49.0/24 | 256 | APNIC | AU | 21st May 2007 |
| 203.20.56.0/24 | 256 | APNIC | AU | 26th Sept 1995 |
| 203.20.61.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.20.64.0/24 | 256 | APNIC | AU | 3rd Oct 1995 |
| 203.20.65.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.20.72.0/24 | 256 | APNIC | AU | 4th Oct 1995 |
| 203.20.84.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.20.88.0/24 | 256 | APNIC | AU | 5th Oct 1995 |
| 203.20.89.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.20.96.0/24 | 256 | APNIC | AU | 5th Oct 1995 |
| 203.20.98.0/24 | 256 | APNIC | AU | 5th Oct 1995 |
| 203.201.176.0/22 | 1k | APNIC |  SG | 27th Jan 2009 |
| 203.201.180.0/24 | 256 | APNIC |  PH | 27th Jan 2009 |
| 203.201.181.0/24 | 256 | APNIC | CN | 9th Jun 2016 |
| 203.201.182.0/24 | 256 | APNIC | CN | 9th Jun 2016 |
| 203.201.188.0/23 | 512 | APNIC |  MM | 11th Aug 2026 |
| 203.201.190.0/23 | 512 | APNIC |  ID | 12th Aug 2026 |
| 203.207.0.0/20 | 4.1k | APNIC |  TW | 19th Dec 2000 |
| 203.207.52.0/22 | 1k | APNIC | ID | 2nd Feb 2009 |
| 203.208.20.0/24 | 256 | APNIC |  HK | 20th Jul 2006 |
| 203.208.22.0/24 | 256 | APNIC | SG | 15th Jun 2006 |
| 203.209.128.0/20 | 4.1k | APNIC | HK | 25th May 2001 |
| 203.209.188.0/23 | 512 | APNIC | ID | 9th Feb 2009 |
| 203.21.0.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.21.10.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.108.0/22 | 1k | APNIC | AU | 16th Apr 2010 |
| 203.21.124.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.128.0/23 | 512 | APNIC | AU | 2nd Nov 1995 |
| 203.21.136.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.21.145.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.156.0/22 | 1k | APNIC | AU | 14th Nov 1995 |
| 203.21.160.0/20 | 4.1k | APNIC | AU | 10th Nov 1995 |
| 203.21.17.0/24 | 256 | APNIC | AU | 20th Oct 1995 |
| 203.21.18.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.2.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.206.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.224.0/19 | 8.2k | APNIC | AU | 14th Nov 1995 |
| 203.21.33.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.34.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.39.0/24 | 256 | APNIC | AU | 23rd Oct 1995 |
| 203.21.41.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.44.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.67.0/24 | 256 | APNIC | AU | 25th Oct 1995 |
| 203.21.68.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.21.69.0/24 | 256 | APNIC | AU | 25th Oct 1995 |
| 203.21.70.0/23 | 512 | APNIC | AU | 25th Oct 1995 |
| 203.21.74.0/23 | 512 | APNIC | ID | 8th Mar 2011 |