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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 203.23.68.0/23 | 512 | APNIC |  AU | 15th Jan 1996 |
| 203.23.73.0/24 | 256 | APNIC |  CN | 14th Apr 2011 |
| 203.23.74.0/24 | 256 | APNIC |  IN | 29th Aug 2025 |
| 203.23.76.0/24 | 256 | APNIC | AU | 15th Jan 1996 |
| 203.23.8.0/24 | 256 | APNIC | AU | 21st Dec 1995 |
| 203.23.85.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.23.92.0/22 | 1k | APNIC | CN | 14th Apr 2011 |
| 203.23.98.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.233.129.0/24 | 256 | APNIC |  KR | 16th Feb 1996 |
| 203.233.130.0/23 | 512 | APNIC | KR | 16th Feb 1996 |
| 203.233.132.0/22 | 1k | APNIC | KR | 16th Feb 1996 |
| 203.233.136.0/21 | 2k | APNIC | KR | 16th Feb 1996 |
| 203.233.144.0/21 | 2k | APNIC | KR | 16th Feb 1996 |
| 203.233.152.0/23 | 512 | APNIC | KR | 16th Feb 1996 |
| 203.233.157.0/24 | 256 | APNIC | KR | 16th Feb 1996 |
| 203.233.158.0/23 | 512 | APNIC | KR | 16th Feb 1996 |
| 203.233.160.0/22 | 1k | APNIC | KR | 16th Feb 1996 |
| 203.233.164.0/24 | 256 | APNIC | KR | 16th Feb 1996 |
| 203.233.166.0/23 | 512 | APNIC | KR | 16th Feb 1996 |
| 203.233.168.0/21 | 2k | APNIC | KR | 16th Feb 1996 |
| 203.233.176.0/20 | 4.1k | APNIC | KR | 16th Feb 1996 |
| 203.233.240.0/20 | 4.1k | APNIC | KR | 16th Feb 1996 |
| 203.235.202.0/23 | 512 | APNIC | KR | 14th Dec 1995 |
| 203.24.111.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.112.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.116.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.120.0/24 | 256 | ARIN |  US | 9th Jun 2021 |
| 203.24.122.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.24.127.0/24 | 256 | APNIC | AU | 22nd Feb 1996 |
| 203.24.129.0/24 | 256 | APNIC | AU | 22nd Feb 1996 |
| 203.24.13.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.130.0/24 | 256 | APNIC | AU | 22nd Feb 1996 |
| 203.24.143.0/24 | 256 | APNIC | AU | 22nd Feb 1996 |
| 203.24.144.0/24 | 256 | APNIC | AU | 22nd Feb 1996 |
| 203.24.145.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.152.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.24.157.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.16.0/24 | 256 | APNIC | AU | 19th Feb 1996 |
| 203.24.161.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.162.0/24 | 256 | APNIC | AU | 26th Feb 1996 |
| 203.24.167.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.172.0/24 | 256 | APNIC | AU | 26th Feb 1996 |
| 203.24.18.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.183.0/24 | 256 | APNIC | AU | 26th Feb 1996 |
| 203.24.186.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.24.199.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.20.0/24 | 256 | APNIC | AU | 20th Feb 1996 |
| 203.24.202.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.24.207.0/24 | 256 | APNIC | AU | 27th Feb 1996 |
| 203.24.208.0/24 | 256 | APNIC | AU | 27th Feb 1996 |