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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
Browse by country
Countries with the most unannounced blocks, largest first.
Unannounced blocks in Japan
1,447 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 125.6.64.0/19 | 8.2k | APNIC |  JP | 4th Aug 2005 |
| 125.6.96.0/20 | 4.1k | APNIC | JP | 4th Aug 2005 |
| 125.62.240.0/20 | 4.1k | APNIC | JP | 10th Oct 2007 |
| 126.188.0.0/15 | 131k | APNIC | JP | 8th Feb 2005 |
| 126.209.192.0/19 | 8.2k | APNIC | JP | 8th Feb 2005 |
| 126.52.100.0/22 | 1k | APNIC | JP | 8th Feb 2005 |
| 126.52.104.0/21 | 2k | APNIC | JP | 8th Feb 2005 |
| 126.52.112.0/20 | 4.1k | APNIC | JP | 8th Feb 2005 |
| 126.52.160.0/19 | 8.2k | APNIC | JP | 8th Feb 2005 |
| 126.52.192.0/18 | 16.4k | APNIC | JP | 8th Feb 2005 |
| 126.52.24.0/22 | 1k | APNIC | JP | 8th Feb 2005 |
| 126.52.28.0/22 | 1k | APNIC | JP | 8th Feb 2005 |
| 126.52.64.0/19 | 8.2k | APNIC | JP | 8th Feb 2005 |
| 126.52.96.0/22 | 1k | APNIC | JP | 8th Feb 2005 |
| 129.136.0.0/16 | 65.5k | APNIC | JP | 11th Dec 1987 |
| 136.198.0.0/16 | 65.5k | APNIC | JP | 25th Sept 1989 |
| 138.243.0.0/16 | 65.5k | APNIC | JP | 11th Jun 1990 |
| 139.154.0.0/16 | 65.5k | APNIC | JP | 7th Feb 1996 |
| 14.102.192.0/19 | 8.2k | APNIC | JP | 20th Sept 2010 |
| 140.81.0.0/16 | 65.5k | APNIC | JP | 23rd Feb 2011 |
| 141.178.0.0/16 | 65.5k | APNIC | JP | 26th Feb 1991 |
| 143.201.0.0/16 | 65.5k | APNIC | JP | 10th Feb 2011 |
| 144.1.0.0/16 | 65.5k | APNIC | JP | 17th Feb 2011 |
| 146.117.0.0/16 | 65.5k | APNIC | JP | 11th Feb 2011 |
| 146.51.0.0/16 | 65.5k | APNIC | JP | 18th Jan 1991 |
| 148.161.0.0/16 | 65.5k | APNIC | JP | 2nd May 1991 |
| 148.59.57.0/24 | 256 | APNIC | JP | 9th Apr 1991 |
| 150.1.0.0/16 | 65.5k | APNIC | JP | 31st Mar 1997 |
| 150.10.0.0/16 | 65.5k | APNIC | JP | 31st Mar 1997 |
| 150.13.0.0/16 | 65.5k | APNIC | JP | 31st Mar 1997 |
| 150.16.0.0/15 | 131k | APNIC | JP | 31st Mar 1997 |
| 150.2.0.0/16 | 65.5k | APNIC | JP | 31st Mar 1997 |
| 150.20.0.0/16 | 65.5k | APNIC | JP | 4th Mar 1993 |
| 150.21.0.0/16 | 65.5k | APNIC | JP | 11th Jul 1994 |
| 150.22.128.0/17 | 32.8k | APNIC | JP | 3rd Nov 1992 |
| 150.22.16.0/20 | 4.1k | APNIC | JP | 3rd Nov 1992 |
| 150.22.32.0/19 | 8.2k | APNIC | JP | 3rd Nov 1992 |
| 150.22.4.0/22 | 1k | APNIC | JP | 3rd Nov 1992 |
| 150.22.64.0/20 | 4.1k | APNIC | JP | 3rd Nov 1992 |
| 150.22.8.0/21 | 2k | APNIC | JP | 3rd Nov 1992 |
| 150.22.80.0/22 | 1k | APNIC | JP | 3rd Nov 1992 |
| 150.22.84.0/22 | 1k | APNIC | JP | 3rd Nov 1992 |
| 150.22.88.0/21 | 2k | APNIC | JP | 3rd Nov 1992 |
| 150.22.96.0/19 | 8.2k | APNIC | JP | 3rd Nov 1992 |
| 150.24.0.0/16 | 65.5k | APNIC | JP | 7th Jun 1996 |
| 150.25.0.0/16 | 65.5k | APNIC | JP | 31st Mar 1997 |
| 150.27.0.0/16 | 65.5k | APNIC | JP | 29th Dec 1992 |
| 150.28.0.0/16 | 65.5k | APNIC | JP | 31st Mar 1997 |
| 150.33.0.0/16 | 65.5k | APNIC | JP | 31st Mar 1997 |
| 150.34.0.0/16 | 65.5k | APNIC | JP | 31st Mar 1997 |