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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,244 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 198.133.100.0/22 | 1k | ARIN |  US | 12th Apr 1993 |
| 198.133.104.0/22 | 1k | ARIN | US | 12th Apr 1993 |
| 198.133.108.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.109.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.110.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.111.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.112.0/23 | 512 | ARIN | US | 12th Apr 1993 |
| 198.133.114.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.115.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.116.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.117.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.118.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.119.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.120.0/24 | 256 | ARIN | US | 12th Apr 1993 |
| 198.133.122.0/24 | 256 | ARIN | US | 13th Apr 1993 |
| 198.133.123.0/24 | 256 | ARIN | US | 13th Apr 1993 |
| 198.133.124.0/24 | 256 | ARIN | US | 13th Apr 1993 |
| 198.133.126.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.133.127.0/24 | 256 | ARIN | US | 14th Apr 1993 |
| 198.133.130.0/24 | 256 | ARIN | US | 15th Apr 1993 |
| 198.133.131.0/24 | 256 | ARIN | US | 15th Apr 1993 |
| 198.133.132.0/22 | 1k | ARIN | US | 16th Apr 1993 |
| 198.133.136.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.133.137.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.133.138.0/24 | 256 | ARIN | US | 16th Apr 1993 |
| 198.133.140.0/24 | 256 | RIPE NCC |  CH | 1st Sept 1993 |
| 198.133.141.0/24 | 256 | ARIN | US | 19th Apr 1993 |
| 198.133.142.0/24 | 256 | ARIN | US | 19th Apr 1993 |
| 198.133.144.0/23 | 512 | ARIN | US | 19th Apr 1993 |
| 198.133.146.0/24 | 256 | ARIN | US | 19th Apr 1993 |
| 198.133.147.0/24 | 256 | ARIN | US | 20th Apr 1993 |
| 198.133.150.0/24 | 256 | ARIN | US | 20th Apr 1993 |
| 198.133.151.0/24 | 256 | ARIN | US | 20th Apr 1993 |
| 198.133.152.0/23 | 512 | ARIN | US | 20th Apr 1993 |
| 198.133.154.0/24 | 256 | ARIN | US | 20th Apr 1993 |
| 198.133.155.0/24 | 256 | ARIN | US | 20th Apr 1993 |
| 198.133.156.0/24 | 256 | ARIN | US | 20th Apr 1993 |
| 198.133.157.0/24 | 256 | ARIN | US | 10th Jan 2014 |
| 198.133.161.0/24 | 256 | ARIN | US | 21st Apr 1993 |
| 198.133.162.0/23 | 512 | ARIN |  CA | 21st Apr 1993 |
| 198.133.164.0/24 | 256 | ARIN | CA | 21st Apr 1993 |
| 198.133.165.0/24 | 256 | ARIN | US | 21st Apr 1993 |
| 198.133.166.0/24 | 256 | ARIN | US | 21st Apr 1993 |
| 198.133.168.0/24 | 256 | ARIN | US | 21st Apr 1993 |
| 198.133.172.0/24 | 256 | ARIN | US | 23rd Apr 1993 |
| 198.133.175.0/24 | 256 | ARIN | US | 23rd Apr 1993 |
| 198.133.176.0/24 | 256 | ARIN | US | 23rd Apr 1993 |
| 198.133.177.0/24 | 256 | ARIN | US | 23rd Apr 1993 |
| 198.133.184.0/24 | 256 | ARIN | US | 27th Apr 1993 |
| 198.133.185.0/24 | 256 | ARIN | US | 27th Apr 1993 |