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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
84,709 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 1.0.1.0/24 | 256 | APNIC |  CN | 14th Apr 2011 |
| 1.0.2.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 1.0.32.0/19 | 8.2k | APNIC | CN | 12th Apr 2011 |
| 1.0.8.0/21 | 2k | APNIC | CN | 12th Apr 2011 |
| 1.1.0.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 1.1.10.0/23 | 512 | APNIC | CN | 12th Apr 2011 |
| 1.1.12.0/22 | 1k | APNIC | CN | 12th Apr 2011 |
| 1.1.16.0/20 | 4.1k | APNIC | CN | 12th Apr 2011 |
| 1.1.2.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 1.1.32.0/19 | 8.2k | APNIC | CN | 12th Apr 2011 |
| 1.1.4.0/22 | 1k | APNIC | CN | 14th Apr 2011 |
| 1.1.9.0/24 | 256 | APNIC | CN | 12th Apr 2011 |
| 1.10.0.0/21 | 2k | APNIC | CN | 12th Apr 2011 |
| 1.10.11.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 1.10.12.0/22 | 1k | APNIC | CN | 14th Apr 2011 |
| 1.10.16.0/20 | 4.1k | APNIC | CN | 12th Apr 2011 |
| 1.10.32.0/19 | 8.2k | APNIC | CN | 12th Apr 2011 |
| 1.10.64.0/18 | 16.4k | APNIC | CN | 12th Apr 2011 |
| 1.10.8.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 1.16.128.0/17 | 32.8k | APNIC |  KR | 12th May 2010 |
| 1.16.64.0/18 | 16.4k | APNIC | KR | 12th May 2010 |
| 1.17.0.0/16 | 65.5k | APNIC | KR | 12th May 2010 |
| 1.178.68.0/22 | 1k | ARIN |  US | 13th Jan 2025 |
| 1.178.72.0/21 | 2k | ARIN | US | 13th Jan 2025 |
| 1.18.0.0/18 | 16.4k | APNIC | KR | 12th May 2010 |
| 1.18.112.0/22 | 1k | APNIC | KR | 12th May 2010 |
| 1.18.136.0/21 | 2k | APNIC | KR | 12th May 2010 |
| 1.18.144.0/20 | 4.1k | APNIC | KR | 12th May 2010 |
| 1.18.160.0/19 | 8.2k | APNIC | KR | 12th May 2010 |
| 1.18.192.0/18 | 16.4k | APNIC | KR | 12th May 2010 |
| 1.18.64.0/19 | 8.2k | APNIC | KR | 12th May 2010 |
| 1.18.96.0/20 | 4.1k | APNIC | KR | 12th May 2010 |
| 1.19.0.0/16 | 65.5k | APNIC | KR | 12th May 2010 |
| 1.2.0.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 1.2.10.0/23 | 512 | APNIC | CN | 12th Apr 2011 |
| 1.2.12.0/22 | 1k | APNIC | CN | 12th Apr 2011 |
| 1.2.16.0/20 | 4.1k | APNIC | CN | 12th Apr 2011 |
| 1.2.2.0/24 | 256 | APNIC | CN | 31st Mar 2011 |
| 1.2.3.0/24 | 256 | APNIC |  AU | 11th Aug 2011 |
| 1.2.32.0/19 | 8.2k | APNIC | CN | 12th Apr 2011 |
| 1.2.5.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 1.2.6.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 1.2.64.0/18 | 16.4k | APNIC | CN | 12th Apr 2011 |
| 1.2.8.0/24 | 256 | APNIC | CN | 12th Apr 2011 |
| 1.2.9.0/24 | 256 | APNIC | CN | 12th Apr 2011 |
| 1.200.0.0/16 | 65.5k | APNIC |  TW | 7th Apr 2011 |
| 1.21.224.0/19 | 8.2k | APNIC |  SG | 16th Jun 2010 |
| 1.3.0.0/16 | 65.5k | APNIC | CN | 12th Apr 2011 |
| 1.32.128.0/18 | 16.4k | APNIC | SG | 5th Apr 2011 |
| 1.4.0.0/24 | 256 | APNIC | AU | 11th Aug 2011 |