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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,221 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.91.86.0/24 | 256 | ARIN |  US | 4th Jan 1991 |
| 192.91.87.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.88.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.89.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.90.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.91.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.92.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.93.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.94.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.95.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.96.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.97.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.98.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.91.99.0/24 | 256 | ARIN | US | 4th Jan 1991 |
| 192.92.10.0/24 | 256 | ARIN | US | 21st Jan 1991 |
| 192.92.100.0/24 | 256 | ARIN | US | 23rd Jan 1991 |
| 192.92.101.0/24 | 256 | ARIN | US | 23rd Jan 1991 |
| 192.92.103.0/24 | 256 | ARIN | US | 23rd Jan 1991 |
| 192.92.104.0/23 | 512 | RIPE NCC |  IT | 23rd Jan 1991 |
| 192.92.107.0/24 | 256 | ARIN | US | 24th Jan 1991 |
| 192.92.108.0/24 | 256 | RIPE NCC |  NL | 25th Jan 1991 |
| 192.92.109.0/24 | 256 | RIPE NCC |  GB | 25th Jan 1991 |
| 192.92.11.0/24 | 256 | ARIN | US | 21st Jan 1991 |
| 192.92.110.0/24 | 256 | ARIN | US | 25th Jan 1991 |
| 192.92.111.0/24 | 256 | ARIN | US | 28th Jan 1991 |
| 192.92.113.0/24 | 256 | ARIN | US | 28th Jan 1991 |
| 192.92.116.0/24 | 256 | RIPE NCC |  FI | 28th Jan 1991 |
| 192.92.12.0/24 | 256 | ARIN | US | 21st Jan 1991 |
| 192.92.120.0/24 | 256 | ARIN | US | 28th Jan 1991 |
| 192.92.121.0/24 | 256 | ARIN | US | 28th Jan 1991 |
| 192.92.123.0/24 | 256 | ARIN | US | 30th Jan 1991 |
| 192.92.127.0/24 | 256 | RIPE NCC | NL | 5th Feb 1991 |
| 192.92.128.0/24 | 256 | RIPE NCC |  CH | 7th Jan 1994 |
| 192.92.130.0/24 | 256 | RIPE NCC |  BE | 5th Feb 1991 |
| 192.92.131.0/24 | 256 | RIPE NCC | NL | 5th Feb 1991 |
| 192.92.132.0/24 | 256 | RIPE NCC | NL | 5th Feb 1991 |
| 192.92.134.0/24 | 256 | RIPE NCC | NL | 9th Jan 1992 |
| 192.92.136.0/24 | 256 | RIPE NCC | NL | 5th Feb 1991 |
| 192.92.137.0/24 | 256 | RIPE NCC | NL | 5th Feb 1991 |
| 192.92.139.0/24 | 256 | RIPE NCC | CH | 5th Feb 1991 |
| 192.92.14.0/24 | 256 | ARIN | US | 21st Jan 1991 |
| 192.92.141.0/24 | 256 | RIPE NCC |  AT | 5th Feb 1991 |
| 192.92.143.0/24 | 256 | RIPE NCC |  PT | 25th Aug 1992 |
| 192.92.145.0/24 | 256 | RIPE NCC | PT | 25th Aug 1992 |
| 192.92.15.0/24 | 256 | APNIC |  ID | 14th Aug 2026 |
| 192.92.150.0/24 | 256 | RIPE NCC | PT | 24th Sept 1992 |
| 192.92.151.0/24 | 256 | RIPE NCC | PT | 24th Sept 1992 |
| 192.92.16.0/24 | 256 | ARIN | US | 21st Jan 1991 |
| 192.92.170.0/24 | 256 | ARIN | US | 5th Feb 1991 |
| 192.92.171.0/24 | 256 | ARIN | US | 5th Feb 1991 |