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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,536 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 203.27.219.0/24 | 256 | APNIC |  AU | 30th May 1996 |
| 203.27.22.0/23 | 512 | APNIC |  CN | 14th Apr 2011 |
| 203.27.222.0/24 | 256 | APNIC | AU | 30th May 1996 |
| 203.27.228.0/24 | 256 | APNIC | AU | 30th May 1996 |
| 203.27.233.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.237.0/24 | 256 | APNIC | AU | 5th Jun 1996 |
| 203.27.241.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.248.0/24 | 256 | APNIC | AU | 5th Jun 1996 |
| 203.27.250.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.35.0/24 | 256 | APNIC | AU | 18th Nov 2008 |
| 203.27.40.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.41.0/24 | 256 | APNIC | AU | 16th May 1996 |
| 203.27.45.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.53.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.6.0/23 | 512 | APNIC |  ID | 11th Mar 2011 |
| 203.27.64.0/24 | 256 | ARIN |  US | 9th Aug 2021 |
| 203.27.65.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.66.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.68.0/24 | 256 | APNIC | AU | 22nd May 1996 |
| 203.27.81.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.85.0/24 | 256 | APNIC | AU | 22nd May 1996 |
| 203.27.88.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.93.0/24 | 256 | APNIC | AU | 24th May 1996 |
| 203.28.0.0/21 | 2k | APNIC | AU | 5th Jun 1996 |
| 203.28.10.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.112.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.12.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.13.0/24 | 256 | APNIC | AU | 5th Jun 1996 |
| 203.28.131.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.134.0/23 | 512 | APNIC |  BD | 28th Mar 2024 |
| 203.28.136.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.140.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.141.0/24 | 256 | APNIC | AU | 24th Jun 1996 |
| 203.28.145.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.151.0/24 | 256 | APNIC |  JP | 10th Apr 2008 |
| 203.28.165.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.169.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.170.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.177.0/24 | 256 | APNIC | AU | 25th Jun 1996 |
| 203.28.178.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.28.185.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.186.0/24 | 256 | APNIC | AU | 25th Jun 1996 |
| 203.28.187.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.191.0/24 | 256 | APNIC | AU | 26th Jun 1996 |
| 203.28.196.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.28.200.0/24 | 256 | APNIC | AU | 26th Jun 1996 |
| 203.28.206.0/24 | 256 | APNIC | AU | 26th Jun 1996 |
| 203.28.208.0/22 | 1k | APNIC | AU | 26th Jun 1996 |
| 203.28.212.0/24 | 256 | APNIC | AU | 26th Jun 1996 |
| 203.28.226.0/23 | 512 | APNIC | CN | 14th Apr 2011 |