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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
84,968 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 131.222.136.0/21 | 2k | RIPE NCC |  US | 6th Apr 1990 |
| 131.222.144.0/20 | 4.1k | RIPE NCC | US | 6th Apr 1990 |
| 131.222.160.0/20 | 4.1k | RIPE NCC | US | 6th Apr 1990 |
| 131.222.176.0/20 | 4.1k | RIPE NCC | US | 6th Apr 1990 |
| 131.222.192.0/23 | 512 | RIPE NCC |  TR | 6th Apr 1990 |
| 131.222.196.0/23 | 512 | RIPE NCC | TR | 6th Apr 1990 |
| 131.222.204.0/23 | 512 | RIPE NCC |  AE | 6th Apr 1990 |
| 131.222.220.0/23 | 512 | RIPE NCC | TR | 6th Apr 1990 |
| 131.222.234.0/23 | 512 | RIPE NCC | TR | 6th Apr 1990 |
| 131.223.0.0/16 | 65.5k | ARIN | US | 27th Jul 2018 |
| 131.235.0.0/16 | 65.5k | ARIN |  CA | 31st Jan 1989 |
| 131.253.0.0/24 | 256 | ARIN | US | 13th Feb 1989 |
| 131.253.10.0/23 | 512 | ARIN | US | 13th Feb 1989 |
| 131.253.16.0/23 | 512 | ARIN | US | 22nd Jun 2011 |
| 131.253.18.0/24 | 256 | ARIN | US | 22nd Jun 2011 |
| 131.253.19.0/24 | 256 | ARIN | US | 13th Feb 1989 |
| 131.253.2.0/24 | 256 | ARIN | US | 13th Feb 1989 |
| 131.253.20.0/24 | 256 | ARIN | US | 13th Feb 1989 |
| 131.253.22.0/23 | 512 | ARIN | US | 22nd Jun 2011 |
| 131.253.4.0/24 | 256 | ARIN | US | 13th Feb 1989 |
| 131.253.48.0/21 | 2k | ARIN | US | 13th Feb 1989 |
| 131.253.56.0/22 | 1k | ARIN | US | 13th Feb 1989 |
| 131.253.60.0/24 | 256 | ARIN | US | 13th Feb 1989 |
| 131.253.7.0/24 | 256 | ARIN | US | 13th Feb 1989 |
| 131.253.9.0/24 | 256 | ARIN | US | 13th Feb 1989 |
| 131.255.128.0/23 | 512 | LACNIC |  AR | 12th Sept 2024 |
| 131.72.112.0/22 | 1k | LACNIC |  CW | 30th Jul 2014 |
| 131.90.0.0/16 | 65.5k | ARIN | US | 31st Oct 1988 |
| 131.97.0.0/16 | 65.5k | RIPE NCC |  SE | 1st Sept 1993 |
| 131.98.0.0/16 | 65.5k | ARIN | US | 2nd Nov 1988 |
| 132.152.0.0/16 | 65.5k | ARIN | US | 17th Feb 1989 |
| 132.158.0.0/16 | 65.5k | ARIN | US | 22nd Feb 1989 |
| 132.173.0.0/16 | 65.5k | ARIN | US | 28th Feb 1989 |
| 132.192.0.0/16 | 65.5k | ARIN | US | 24th Oct 2024 |
| 132.201.0.0/16 | 65.5k | ARIN | US | 14th Mar 1989 |
| 132.202.0.0/16 | 65.5k | ARIN | CA | 31st May 1989 |
| 132.224.0.0/16 | 65.5k | ARIN | US | 17th Mar 1989 |
| 132.233.0.0/16 | 65.5k | ARIN | US | 23rd Mar 1989 |
| 132.237.0.0/17 | 32.8k | ARIN | US | 24th Mar 1989 |
| 132.240.0.0/16 | 65.5k | ARIN | US | 27th Mar 1989 |
| 132.243.0.0/20 | 4.1k | RIPE NCC | US | 29th Mar 1989 |
| 132.243.128.0/19 | 8.2k | RIPE NCC | US | 29th Mar 1989 |
| 132.243.184.0/21 | 2k | RIPE NCC |  AM | 29th Mar 1989 |
| 132.243.32.0/19 | 8.2k | ARIN | US | 29th Mar 1989 |
| 132.243.96.0/20 | 4.1k | RIPE NCC | US | 29th Mar 1989 |
| 132.253.0.0/16 | 65.5k | ARIN | US | 5th Apr 1989 |
| 132.255.0.0/22 | 1k | LACNIC |  PE | 12th Nov 2014 |
| 134.0.224.0/19 | 8.2k | RIPE NCC |  OM | 1st Nov 2011 |
| 134.116.0.0/16 | 65.5k | ARIN | US | 25th May 1989 |
| 134.119.128.0/19 | 8.2k | RIPE NCC |  DE | 1st Jan 1984 |