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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 192.146.149.0/24 | 256 | ARIN |  US | 1st Jul 2026 |
| 192.146.151.0/24 | 256 | ARIN | US | 30th Jan 1992 |
| 192.146.152.0/24 | 256 | RIPE NCC |  FI | 13th May 1992 |
| 192.146.153.0/24 | 256 | ARIN | US | 30th Jan 1992 |
| 192.146.157.0/24 | 256 | LACNIC |  BR | 30th Jan 1992 |
| 192.146.158.0/24 | 256 | ARIN | US | 30th Jan 1992 |
| 192.146.159.0/24 | 256 | ARIN | US | 13th May 1992 |
| 192.146.160.0/24 | 256 | ARIN | US | 30th Jan 1992 |
| 192.146.161.0/24 | 256 | ARIN | US | 30th Jan 1992 |
| 192.146.162.0/24 | 256 | ARIN | US | 30th Jan 1992 |
| 192.146.173.0/24 | 256 | RIPE NCC |  IT | 3rd Feb 1992 |
| 192.146.174.0/24 | 256 | RIPE NCC | IT | 3rd Feb 1992 |
| 192.146.175.0/24 | 256 | RIPE NCC | IT | 3rd Feb 1992 |
| 192.146.176.0/24 | 256 | RIPE NCC | IT | 3rd Feb 1992 |
| 192.146.177.0/24 | 256 | RIPE NCC | IT | 3rd Feb 1992 |
| 192.146.178.0/24 | 256 | RIPE NCC | IT | 3rd Feb 1992 |
| 192.146.179.0/24 | 256 | RIPE NCC | IT | 3rd Feb 1992 |
| 192.146.180.0/24 | 256 | RIPE NCC | IT | 3rd Feb 1992 |
| 192.146.181.0/24 | 256 | RIPE NCC | IT | 3rd Feb 1992 |
| 192.146.182.0/24 | 256 | RIPE NCC |  FR | 3rd Feb 1992 |
| 192.146.184.0/24 | 256 | APNIC |  JP | 3rd Feb 1992 |
| 192.146.185.0/24 | 256 | RIPE NCC |  DE | 3rd Feb 1992 |
| 192.146.187.0/24 | 256 | RIPE NCC |  ES | 3rd Feb 1992 |
| 192.146.188.0/24 | 256 | ARIN | US | 3rd Feb 1992 |
| 192.146.189.0/24 | 256 | APNIC |  IN | 17th Aug 2026 |
| 192.146.193.0/24 | 256 | RIPE NCC |  NO | 4th Feb 1992 |
| 192.146.194.0/24 | 256 | ARIN | US | 4th Feb 1992 |
| 192.146.195.0/24 | 256 | ARIN | US | 4th Feb 1992 |
| 192.146.196.0/24 | 256 | ARIN | US | 4th Feb 1992 |
| 192.146.201.0/24 | 256 | ARIN | US | 4th Feb 1992 |
| 192.146.202.0/24 | 256 | ARIN | US | 4th Feb 1992 |
| 192.146.204.0/24 | 256 | RIPE NCC |  CZ | 4th Feb 1992 |
| 192.146.205.0/24 | 256 | ARIN | US | 4th Feb 1992 |
| 192.146.207.0/24 | 256 | ARIN | US | 4th Feb 1992 |
| 192.146.208.0/24 | 256 | ARIN | US | 5th Feb 1992 |
| 192.146.209.0/24 | 256 | ARIN | US | 5th Feb 1992 |
| 192.146.210.0/24 | 256 | ARIN | US | 5th Feb 1992 |
| 192.146.211.0/24 | 256 | ARIN | US | 5th Feb 1992 |
| 192.146.212.0/24 | 256 | ARIN | US | 5th Feb 1992 |
| 192.146.220.0/22 | 1k | ARIN | US | 12th Nov 1996 |
| 192.146.224.0/23 | 512 | ARIN | US | 12th Nov 1996 |
| 192.146.227.0/24 | 256 | RIPE NCC | NO | 7th Feb 1992 |
| 192.146.228.0/24 | 256 | RIPE NCC |  GB | 7th Feb 1992 |
| 192.146.232.0/24 | 256 | APNIC |  AU | 24th Jan 2011 |
| 192.146.233.0/24 | 256 | RIPE NCC | FR | 8th Feb 1992 |
| 192.146.234.0/24 | 256 | RIPE NCC | FR | 8th Feb 1992 |
| 192.146.235.0/24 | 256 | ARIN | US | 8th Feb 1992 |
| 192.146.236.0/24 | 256 | ARIN | US | 8th Feb 1992 |
| 192.146.237.0/24 | 256 | LACNIC |  UY | 8th Feb 1992 |
| 192.146.241.0/24 | 256 | ARIN | US | 8th Feb 1992 |