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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 unannounced space registered through ARIN, largest first.
Unannounced blocks registered through ARIN
30,441 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.135.44.0/24 | 256 | ARIN |  US | 21st Nov 1991 |
| 192.135.45.0/24 | 256 | ARIN | US | 29th Mar 1992 |
| 192.135.47.0/24 | 256 | ARIN | US | 21st Nov 1991 |
| 192.135.48.0/24 | 256 | ARIN |  CA | 21st Nov 1991 |
| 192.135.49.0/24 | 256 | ARIN | US | 21st Nov 1991 |
| 192.135.54.0/23 | 512 | ARIN | US | 28th Jan 2015 |
| 192.135.6.0/24 | 256 | ARIN | US | 29th Mar 1992 |
| 192.135.65.0/24 | 256 | ARIN | US | 26th Nov 1991 |
| 192.135.67.0/24 | 256 | ARIN | US | 26th Nov 1991 |
| 192.135.69.0/24 | 256 | ARIN | US | 27th Nov 1991 |
| 192.135.70.0/24 | 256 | ARIN | US | 27th Nov 1991 |
| 192.135.71.0/24 | 256 | ARIN | US | 20th May 1992 |
| 192.135.72.0/22 | 1k | ARIN | US | 20th May 1992 |
| 192.135.77.0/24 | 256 | ARIN | CA | 5th May 1992 |
| 192.135.78.0/24 | 256 | ARIN | US | 3rd Dec 1991 |
| 192.135.81.0/24 | 256 | ARIN | US | 3rd Dec 1991 |
| 192.135.83.0/24 | 256 | ARIN | CA | 18th Dec 1991 |
| 192.135.85.0/24 | 256 | ARIN | US | 5th Dec 1991 |
| 192.135.87.0/24 | 256 | ARIN | US | 5th Dec 1991 |
| 192.135.88.0/24 | 256 | ARIN | US | 5th Dec 1991 |
| 192.135.93.0/24 | 256 | ARIN | US | 28th Apr 2015 |
| 192.136.1.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.10.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.106.0/24 | 256 | ARIN | US | 8th Jan 1992 |
| 192.136.107.0/24 | 256 | ARIN | US | 8th Jan 1992 |
| 192.136.11.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.112.0/24 | 256 | ARIN | US | 14th Feb 1992 |
| 192.136.114.0/23 | 512 | ARIN | CA | 13th Jan 1992 |
| 192.136.12.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.135.0/24 | 256 | ARIN | US | 28th Apr 2015 |
| 192.136.14.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.150.0/24 | 256 | ARIN | US | 7th Feb 1992 |
| 192.136.151.0/24 | 256 | ARIN | US | 7th Feb 1992 |
| 192.136.152.0/24 | 256 | ARIN | US | 7th Feb 1992 |
| 192.136.17.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.2.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.20.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.21.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.25.0/24 | 256 | ARIN | US | 23rd Dec 1991 |
| 192.136.26.0/24 | 256 | ARIN | US | 23rd Dec 1991 |
| 192.136.28.0/24 | 256 | ARIN | US | 23rd Dec 1991 |
| 192.136.3.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.32.0/24 | 256 | ARIN | US | 23rd Dec 1991 |
| 192.136.33.0/24 | 256 | ARIN | US | 23rd Dec 1991 |
| 192.136.34.0/24 | 256 | ARIN | US | 23rd Dec 1991 |
| 192.136.35.0/24 | 256 | ARIN | US | 23rd Dec 1991 |
| 192.136.37.0/24 | 256 | ARIN | US | 23rd Dec 1991 |
| 192.136.38.0/24 | 256 | ARIN | US | 23rd Dec 1991 |
| 192.136.4.0/24 | 256 | ARIN | US | 19th Dec 1991 |
| 192.136.5.0/24 | 256 | ARIN | US | 19th Dec 1991 |