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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 203.121.158.0/24 | 256 | APNIC |  JP | 24th Mar 2000 |
| 203.121.167.0/24 | 256 | APNIC | JP | 17th Jan 2003 |
| 203.121.170.0/24 | 256 | APNIC | JP | 17th Jan 2003 |
| 203.121.175.0/24 | 256 | APNIC | JP | 17th Jan 2003 |
| 203.121.176.0/23 | 512 | APNIC | JP | 17th Jan 2003 |
| 203.121.181.0/24 | 256 | APNIC | JP | 17th Jan 2003 |
| 203.121.183.0/24 | 256 | APNIC | JP | 17th Jan 2003 |
| 203.121.184.0/24 | 256 | APNIC | JP | 17th Jan 2003 |
| 203.121.187.0/24 | 256 | APNIC | JP | 17th Jan 2003 |
| 203.121.189.0/24 | 256 | APNIC | JP | 17th Jan 2003 |
| 203.121.190.0/23 | 512 | APNIC | JP | 17th Jan 2003 |
| 203.122.64.0/19 | 8.2k | APNIC |  AU | 12th Sept 2002 |
| 203.122.96.0/19 | 8.2k | APNIC | AU | 3rd Oct 2003 |
| 203.123.58.0/24 | 256 | APNIC |  CN | 9th Jun 2016 |
| 203.123.59.0/24 | 256 | APNIC | AU | 7th Mar 2008 |
| 203.124.24.0/21 | 2k | APNIC |  PK | 22nd Mar 2006 |
| 203.124.6.0/23 | 512 | APNIC | JP | 26th Mar 2007 |
| 203.124.96.0/19 | 8.2k | APNIC |  SG | 19th Apr 2010 |
| 203.128.128.0/19 | 8.2k | APNIC | AU | 11th Apr 2011 |
| 203.128.232.0/22 | 1k | APNIC | AU | 5th Mar 2008 |
| 203.128.32.0/19 | 8.2k | APNIC | CN | 11th Mar 2005 |
| 203.128.96.0/19 | 8.2k | APNIC | CN | 14th Mar 2005 |
| 203.129.160.0/19 | 8.2k | APNIC | JP | 15th Mar 2005 |
| 203.13.166.0/24 | 256 | APNIC | AU | 21st Mar 1995 |
| 203.13.172.0/24 | 256 | APNIC | AU | 21st Mar 1995 |
| 203.13.173.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.13.174.0/24 | 256 | APNIC | AU | 22nd Mar 1995 |
| 203.13.18.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.13.21.0/24 | 256 | APNIC | AU | 27th Feb 1995 |
| 203.13.224.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.13.226.0/24 | 256 | APNIC | AU | 26th Jul 1995 |
| 203.13.227.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.13.229.0/24 | 256 | APNIC | AU | 27th Mar 1995 |
| 203.13.230.0/24 | 256 | APNIC | AU | 27th Mar 1995 |
| 203.13.233.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.13.24.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.13.36.0/24 | 256 | APNIC | AU | 1st Mar 1995 |
| 203.13.38.0/24 | 256 | APNIC | AU | 1st Mar 1995 |
| 203.13.44.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.13.88.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.13.91.0/24 | 256 | APNIC | AU | 12th Mar 1995 |
| 203.13.92.0/22 | 1k | APNIC | CN | 14th Apr 2011 |
| 203.131.0.0/19 | 8.2k | APNIC | AU | 4th Mar 1998 |
| 203.132.8.0/21 | 2k | APNIC | AU | 7th May 1998 |
| 203.133.252.0/22 | 1k | APNIC | PK | 25th Apr 1996 |
| 203.134.224.0/21 | 2k | APNIC |  IN | 27th Mar 2006 |
| 203.134.240.0/21 | 2k | APNIC | CN | 2nd Aug 2005 |
| 203.135.160.0/20 | 4.1k | APNIC | CN | 19th May 2005 |
| 203.135.189.0/24 | 256 | APNIC | SG | 16th Jun 2009 |
| 203.14.103.0/24 | 256 | APNIC | AU | 17th Apr 1995 |