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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,041 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 165.153.0.0/16 | 65.5k | ARIN |  US | 17th Jun 1993 |
| 165.157.0.0/16 | 65.5k | ARIN | US | 21st Jun 1993 |
| 165.163.0.0/16 | 65.5k | ARIN | US | 25th Jun 1993 |
| 165.164.0.0/16 | 65.5k | ARIN | US | 28th Jun 1993 |
| 165.167.0.0/16 | 65.5k | ARIN | US | 11th Sept 2018 |
| 165.168.0.0/16 | 65.5k | ARIN | US | 6th Jul 1993 |
| 165.172.0.0/16 | 65.5k | ARIN | US | 8th Jul 1993 |
| 165.174.0.0/16 | 65.5k | ARIN | US | 12th Jul 1993 |
| 165.176.0.0/16 | 65.5k | ARIN | US | 19th Jul 1993 |
| 165.177.0.0/16 | 65.5k | ARIN | US | 19th Jul 1993 |
| 165.179.0.0/16 | 65.5k | ARIN | US | 21st Jul 1993 |
| 165.180.0.0/16 | 65.5k | AFRINIC |  ZA | 23rd Jul 1993 |
| 165.188.0.0/18 | 16.4k | ARIN | US | 27th Aug 1993 |
| 165.198.0.0/16 | 65.5k | ARIN | US | 16th Aug 1993 |
| 165.2.0.0/18 | 16.4k | ARIN | US | 24th Mar 1993 |
| 165.2.88.0/21 | 2k | ARIN | US | 24th Mar 1993 |
| 165.203.0.0/16 | 65.5k | ARIN | US | 25th Aug 1993 |
| 165.205.0.0/16 | 65.5k | APNIC |  NZ | 27th Aug 1993 |
| 165.217.144.0/20 | 4.1k | ARIN | US | 7th Sept 1993 |
| 165.217.64.0/22 | 1k | RIPE NCC | US | 7th Sept 1993 |
| 165.217.68.0/22 | 1k | RIPE NCC | US | 7th Sept 1993 |
| 165.217.72.0/22 | 1k | RIPE NCC | US | 7th Sept 1993 |
| 165.217.76.0/22 | 1k | RIPE NCC | US | 7th Sept 1993 |
| 165.217.80.0/22 | 1k | RIPE NCC | US | 7th Sept 1993 |
| 165.217.84.0/22 | 1k | RIPE NCC | US | 7th Sept 1993 |
| 165.217.88.0/22 | 1k | RIPE NCC | US | 7th Sept 1993 |
| 165.217.92.0/22 | 1k | RIPE NCC | US | 7th Sept 1993 |
| 165.218.0.0/16 | 65.5k | RIPE NCC |  DE | 1st Sept 1993 |
| 165.238.0.0/16 | 65.5k | ARIN | US | 1st Oct 1993 |
| 165.240.0.0/16 | 65.5k | APNIC |  AU | 4th Oct 1993 |
| 165.250.0.0/16 | 65.5k | ARIN |  JE | 13th Oct 1993 |
| 165.28.0.0/16 | 65.5k | ARIN | US | 6th Apr 1993 |
| 165.30.0.0/16 | 65.5k | ARIN | US | 8th Apr 1993 |
| 165.31.0.0/16 | 65.5k | APNIC | AU | 9th Apr 1993 |
| 165.32.0.0/13 | 524k | ARIN | US | 11th Feb 1993 |
| 165.40.0.0/15 | 131k | ARIN | US | 11th Feb 1993 |
| 165.42.0.0/15 | 131k | APNIC |  IN | 11th Feb 1993 |
| 165.44.0.0/14 | 262k | ARIN | US | 11th Feb 1993 |
| 165.48.0.0/16 | 65.5k | ARIN | US | 11th Feb 1993 |
| 165.64.0.0/16 | 65.5k | ARIN | US | 9th Apr 1993 |
| 165.65.196.0/22 | 1k | RIPE NCC |  GB | 12th Apr 1993 |
| 165.65.200.0/22 | 1k | RIPE NCC | GB | 12th Apr 1993 |
| 165.7.0.0/16 | 65.5k | ARIN | US | 26th Mar 1993 |
| 165.71.0.0/16 | 65.5k | ARIN | US | 15th Apr 1993 |
| 165.77.0.0/16 | 65.5k | ARIN | US | 22nd Apr 1993 |
| 165.80.0.0/16 | 65.5k | ARIN | US | 26th Apr 1993 |
| 165.84.224.0/21 | 2k | RIPE NCC | GB | 16th Feb 2016 |
| 165.84.32.0/20 | 4.1k | APNIC | NZ | 27th Apr 1993 |
| 165.96.0.0/16 | 65.5k | APNIC |  JP | 10th May 1993 |
| 165.99.10.0/23 | 512 | APNIC | IN | 7th May 2025 |