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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,149 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.197.193.0/24 | 256 | ARIN |  CA | 29th Jan 1993 |
| 192.197.194.0/23 | 512 | ARIN | CA | 16th Apr 1997 |
| 192.197.197.0/24 | 256 | ARIN | CA | 26th Mar 1993 |
| 192.197.198.0/24 | 256 | ARIN | CA | 30th Mar 1993 |
| 192.197.199.0/24 | 256 | ARIN |  US | 30th Mar 1993 |
| 192.197.200.0/24 | 256 | ARIN | US | 30th Mar 1993 |
| 192.197.202.0/24 | 256 | ARIN | CA | 30th Mar 1993 |
| 192.197.203.0/24 | 256 | ARIN | CA | 30th Mar 1993 |
| 192.197.204.0/24 | 256 | ARIN | CA | 30th Mar 1993 |
| 192.197.206.0/24 | 256 | ARIN | CA | 4th Feb 1993 |
| 192.197.208.0/24 | 256 | ARIN | CA | 19th Feb 1993 |
| 192.197.210.0/24 | 256 | ARIN | CA | 19th Jul 1992 |
| 192.197.211.0/24 | 256 | ARIN | CA | 19th Jul 1992 |
| 192.197.214.0/24 | 256 | ARIN | CA | 19th Jul 1992 |
| 192.197.215.0/24 | 256 | ARIN | CA | 19th Jul 1992 |
| 192.197.224.0/24 | 256 | ARIN | US | 26th Feb 1993 |
| 192.197.230.0/23 | 512 | ARIN | CA | 15th Mar 1994 |
| 192.197.233.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.197.234.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.197.235.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.197.236.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.197.237.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.197.238.0/24 | 256 | ARIN | CA | 2nd Dec 1992 |
| 192.197.239.0/24 | 256 | ARIN | CA | 9th Feb 1993 |
| 192.197.240.0/24 | 256 | ARIN | CA | 9th Feb 1993 |
| 192.197.241.0/24 | 256 | ARIN | CA | 9th Feb 1993 |
| 192.197.242.0/24 | 256 | ARIN | CA | 9th Feb 1993 |
| 192.197.244.0/24 | 256 | ARIN | CA | 3rd May 1993 |
| 192.197.246.0/24 | 256 | ARIN | CA | 19th Jul 1992 |
| 192.197.248.0/24 | 256 | ARIN | CA | 30th Nov 1993 |
| 192.197.249.0/24 | 256 | ARIN | CA | 21st Apr 1993 |
| 192.197.252.0/24 | 256 | ARIN | CA | 17th Mar 1993 |
| 192.197.254.0/24 | 256 | ARIN | CA | 17th Mar 1993 |
| 192.197.52.0/23 | 512 | ARIN | CA | 26th Oct 1992 |
| 192.197.55.0/24 | 256 | ARIN | CA | 27th Oct 1992 |
| 192.197.56.0/24 | 256 | ARIN | CA | 28th Oct 1992 |
| 192.197.57.0/24 | 256 | ARIN | CA | 28th Oct 1992 |
| 192.197.63.0/24 | 256 | ARIN | CA | 26th Oct 1992 |
| 192.197.65.0/24 | 256 | ARIN | CA | 26th Oct 1992 |
| 192.197.66.0/24 | 256 | ARIN | CA | 26th Oct 1992 |
| 192.197.67.0/24 | 256 | ARIN | CA | 26th Oct 1992 |
| 192.197.68.0/24 | 256 | ARIN | CA | 9th Mar 1993 |
| 192.197.70.0/24 | 256 | ARIN | CA | 9th Mar 1993 |
| 192.197.73.0/24 | 256 | ARIN | CA | 10th Mar 1993 |
| 192.197.74.0/24 | 256 | ARIN | CA | 10th Mar 1993 |
| 192.197.75.0/24 | 256 | ARIN | CA | 10th Mar 1993 |
| 192.197.78.0/23 | 512 | ARIN | CA | 12th Aug 1993 |
| 192.197.80.0/23 | 512 | ARIN | CA | 12th Aug 1993 |
| 192.197.84.0/24 | 256 | ARIN | CA | 12th Aug 1993 |
| 192.197.85.0/24 | 256 | ARIN | CA | 17th Mar 1993 |