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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 203.26.204.0/24 | 256 | APNIC |  PH | 6th May 1996 |
| 203.26.210.0/24 | 256 | APNIC |  CN | 14th Apr 2011 |
| 203.26.214.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.217.0/24 | 256 | APNIC |  AU | 8th May 1996 |
| 203.26.222.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.224.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.228.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.232.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.34.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.36.0/24 | 256 | APNIC | AU | 9th Apr 1996 |
| 203.26.39.0/24 | 256 | APNIC | AU | 9th Apr 1996 |
| 203.26.40.0/24 | 256 | APNIC |  HK | 10th Apr 1996 |
| 203.26.42.0/23 | 512 | APNIC | AU | 10th Apr 1996 |
| 203.26.49.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.50.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.55.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.56.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.26.60.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.65.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.66.0/23 | 512 | APNIC | AU | 18th Apr 1996 |
| 203.26.68.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.70.0/24 | 256 | APNIC | AU | 18th Apr 1996 |
| 203.26.76.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.77.0/24 | 256 | APNIC |  PK | 2nd Aug 2005 |
| 203.26.78.0/24 | 256 | APNIC |  ID | 11th Aug 2026 |
| 203.26.80.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.84.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.26.97.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.0.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.10.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.100.0/24 | 256 | APNIC | AU | 24th May 1996 |
| 203.27.102.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.103.0/24 | 256 | APNIC | AU | 27th May 1996 |
| 203.27.108.0/24 | 256 | APNIC | AU | 27th May 1996 |
| 203.27.109.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.111.0/24 | 256 | APNIC | AU | 27th May 1996 |
| 203.27.117.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.121.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.122.0/23 | 512 | APNIC | CN | 14th Apr 2011 |
| 203.27.124.0/24 | 256 | ARIN |  US | 23rd Feb 2026 |
| 203.27.125.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.15.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.16.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.192.0/24 | 256 | APNIC | AU | 27th May 1996 |
| 203.27.194.0/24 | 256 | APNIC | AU | 27th May 1996 |
| 203.27.20.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.200.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.202.0/24 | 256 | APNIC | CN | 14th Apr 2011 |
| 203.27.204.0/24 | 256 | APNIC | AU | 28th May 1996 |
| 203.27.208.0/21 | 2k | APNIC | AU | 28th May 1996 |