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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,075 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 174.128.200.0/22 | 1k | ARIN |  US | 4th Jun 2026 |
| 174.128.204.0/22 | 1k | ARIN | US | 1st Jul 2010 |
| 174.136.112.0/20 | 4.1k | ARIN |  CA | 18th Nov 2010 |
| 174.136.240.0/22 | 1k | ARIN | CA | 1st Apr 2024 |
| 174.136.250.0/23 | 512 | ARIN | CA | 7th Jan 2022 |
| 174.138.144.0/20 | 4.1k | APNIC |  HK | 31st Dec 2009 |
| 174.34.229.0/24 | 256 | ARIN | CA | 10th Dec 2019 |
| 174.34.233.0/24 | 256 | ARIN | US | 22nd Sept 2020 |
| 174.34.255.0/24 | 256 | ARIN | US | 18th Apr 2019 |
| 174.8.0.0/13 | 524k | ARIN | US | 7th Jan 2009 |
| 175.100.224.0/19 | 8.2k | APNIC |  JP | 4th Jan 2010 |
| 175.103.130.0/23 | 512 | APNIC | JP | 4th Jan 2010 |
| 175.103.132.0/23 | 512 | APNIC | JP | 4th Jan 2010 |
| 175.103.134.0/23 | 512 | APNIC | JP | 4th Jan 2010 |
| 175.103.136.0/21 | 2k | APNIC | JP | 4th Jan 2010 |
| 175.103.152.0/22 | 1k | APNIC | JP | 4th Jan 2010 |
| 175.103.156.0/23 | 512 | APNIC | JP | 4th Jan 2010 |
| 175.103.158.0/24 | 256 | APNIC | JP | 4th Jan 2010 |
| 175.103.159.0/24 | 256 | APNIC | JP | 4th Jan 2010 |
| 175.103.160.0/22 | 1k | APNIC | JP | 4th Jan 2010 |
| 175.103.166.0/23 | 512 | APNIC | JP | 4th Jan 2010 |
| 175.103.168.0/22 | 1k | APNIC | JP | 4th Jan 2010 |
| 175.103.172.0/23 | 512 | APNIC | JP | 4th Jan 2010 |
| 175.103.174.0/23 | 512 | APNIC | JP | 4th Jan 2010 |
| 175.103.178.0/23 | 512 | APNIC | JP | 4th Jan 2010 |
| 175.103.192.0/20 | 4.1k | APNIC | JP | 4th Jan 2010 |
| 175.103.208.0/21 | 2k | APNIC | JP | 4th Jan 2010 |
| 175.103.4.0/22 | 1k | APNIC | JP | 4th Jan 2010 |
| 175.103.64.0/18 | 16.4k | APNIC |  VN | 11th Apr 2011 |
| 175.106.128.0/17 | 32.8k | APNIC |  CN | 5th Jan 2010 |
| 175.106.28.0/22 | 1k | APNIC |  AU | 15th Feb 2011 |
| 175.107.64.0/18 | 16.4k | APNIC |  KR | 12th Jan 2010 |
| 175.111.104.0/22 | 1k | APNIC |  SG | 14th Jan 2010 |
| 175.111.144.0/22 | 1k | APNIC | CN | 29th Jan 2016 |
| 175.111.148.0/22 | 1k | APNIC | CN | 29th Jan 2016 |
| 175.111.152.0/22 | 1k | APNIC | CN | 29th Jan 2016 |
| 175.111.156.0/22 | 1k | APNIC | CN | 29th Jan 2016 |
| 175.111.160.0/22 | 1k | APNIC | CN | 29th Jan 2016 |
| 175.111.164.0/22 | 1k | APNIC | CN | 29th Jan 2016 |
| 175.111.168.0/22 | 1k | APNIC | CN | 29th Jan 2016 |
| 175.111.172.0/22 | 1k | APNIC | CN | 29th Jan 2016 |
| 175.111.184.0/22 | 1k | APNIC | CN | 29th Jan 2016 |
| 175.111.32.0/19 | 8.2k | APNIC |  TW | 13th Jan 2010 |
| 175.111.98.0/23 | 512 | APNIC |  ID | 13th Oct 2023 |
| 175.158.96.0/22 | 1k | APNIC | CN | 19th Nov 2015 |
| 175.176.152.0/22 | 1k | APNIC | HK | 19th Nov 2015 |
| 175.176.156.0/22 | 1k | APNIC | CN | 19th Nov 2015 |
| 175.176.176.0/22 | 1k | APNIC | CN | 30th Nov 2015 |
| 175.176.188.0/22 | 1k | APNIC | CN | 1st Dec 2015 |
| 175.176.224.0/19 | 8.2k | APNIC | SG | 28th Jan 2010 |