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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,124 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.138.9.0/24 | 256 | ARIN |  US | 6th May 2015 |
| 192.138.90.0/23 | 512 | ARIN | US | 23rd Jan 1996 |
| 192.138.92.0/22 | 1k | ARIN | US | 23rd Jan 1996 |
| 192.138.96.0/23 | 512 | ARIN | US | 23rd Jan 1996 |
| 192.138.98.0/24 | 256 | ARIN | US | 23rd Jan 1996 |
| 192.138.99.0/24 | 256 | ARIN | US | 30th Apr 2015 |
| 192.139.0.0/24 | 256 | ARIN | US | 4th May 2015 |
| 192.139.1.0/24 | 256 | ARIN |  CA | 10th Jan 1992 |
| 192.139.112.0/23 | 512 | ARIN | CA | 13th May 1992 |
| 192.139.115.0/24 | 256 | ARIN | CA | 4th May 1992 |
| 192.139.124.0/24 | 256 | ARIN | CA | 14th May 1992 |
| 192.139.125.0/24 | 256 | ARIN | CA | 24th Jul 1995 |
| 192.139.130.0/24 | 256 | ARIN | CA | 26th May 1992 |
| 192.139.131.0/24 | 256 | ARIN | US | 22nd May 2015 |
| 192.139.138.0/24 | 256 | ARIN | CA | 29th May 1992 |
| 192.139.14.0/24 | 256 | ARIN | CA | 28th Jan 1992 |
| 192.139.142.0/24 | 256 | ARIN | CA | 17th Jun 1992 |
| 192.139.143.0/24 | 256 | ARIN | CA | 22nd Jun 1992 |
| 192.139.144.0/24 | 256 | ARIN | CA | 23rd Jun 1992 |
| 192.139.146.0/24 | 256 | ARIN | CA | 23rd Jun 1992 |
| 192.139.147.0/24 | 256 | ARIN | US | 6th May 2015 |
| 192.139.151.0/24 | 256 | ARIN | CA | 23rd Jul 1992 |
| 192.139.155.0/24 | 256 | ARIN | US | 10th Aug 1992 |
| 192.139.165.0/24 | 256 | ARIN | CA | 5th Feb 2024 |
| 192.139.176.0/21 | 2k | ARIN | CA | 13th Mar 2026 |
| 192.139.186.0/24 | 256 | ARIN | CA | 21st Oct 1992 |
| 192.139.189.0/24 | 256 | ARIN | US | 6th May 2015 |
| 192.139.197.0/24 | 256 | ARIN | CA | 10th Aug 1992 |
| 192.139.199.0/24 | 256 | ARIN | CA | 10th Aug 1992 |
| 192.139.2.0/24 | 256 | ARIN | CA | 10th Jan 1992 |
| 192.139.200.0/24 | 256 | ARIN | CA | 30th Dec 1992 |
| 192.139.201.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.139.203.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.139.204.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.139.206.0/24 | 256 | ARIN | CA | 12th Aug 1992 |
| 192.139.207.0/24 | 256 | ARIN | CA | 12th Aug 1992 |
| 192.139.208.0/24 | 256 | ARIN | CA | 10th Aug 1992 |
| 192.139.209.0/24 | 256 | ARIN | CA | 10th Aug 1992 |
| 192.139.210.0/24 | 256 | ARIN | CA | 10th Aug 1992 |
| 192.139.211.0/24 | 256 | ARIN | CA | 10th Aug 1992 |
| 192.139.212.0/24 | 256 | ARIN | CA | 10th Aug 1992 |
| 192.139.217.0/24 | 256 | ARIN | US | 26th Aug 1992 |
| 192.139.218.0/24 | 256 | ARIN | CA | 18th Aug 1992 |
| 192.139.22.0/24 | 256 | ARIN | CA | 19th Feb 1992 |
| 192.139.225.0/24 | 256 | ARIN | CA | 31st Aug 1992 |
| 192.139.226.0/24 | 256 | ARIN | CA | 31st Aug 1992 |
| 192.139.227.0/24 | 256 | ARIN | CA | 31st Aug 1992 |
| 192.139.228.0/24 | 256 | ARIN | CA | 2nd Sept 1992 |
| 192.139.229.0/24 | 256 | ARIN | CA | 2nd Sept 1992 |
| 192.139.23.0/24 | 256 | ARIN | CA | 18th Feb 1992 |