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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,001 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 152.235.128.0/17 | 32.8k | APNIC |  SG | 20th Feb 2025 |
| 152.237.0.0/18 | 16.4k | LACNIC |  BR | 15th May 2014 |
| 152.237.128.0/18 | 16.4k | LACNIC | BR | 15th May 2014 |
| 152.237.192.0/20 | 4.1k | LACNIC | BR | 13th Mar 2025 |
| 152.237.64.0/19 | 8.2k | RIPE NCC |  LT | 6th Mar 2025 |
| 152.237.96.0/19 | 8.2k | LACNIC | BR | 15th May 2014 |
| 152.238.0.0/16 | 65.5k | ARIN |  US | 29th Jul 2026 |
| 152.239.128.0/17 | 32.8k | ARIN | US | 29th Jul 2026 |
| 152.36.16.0/20 | 4.1k | ARIN | US | 21st Jul 2026 |
| 152.36.32.0/19 | 8.2k | ARIN | US | 10th Jan 1992 |
| 152.36.64.0/18 | 16.4k | ARIN | US | 10th Jan 1992 |
| 152.36.8.0/21 | 2k | ARIN | US | 11th Aug 2026 |
| 152.55.0.0/18 | 16.4k | ARIN | US | 28th Jul 2026 |
| 152.55.156.0/22 | 1k | RIPE NCC |  BE | 8th Aug 1994 |
| 152.55.192.0/20 | 4.1k | ARIN | US | 23rd Jan 2026 |
| 152.55.248.0/22 | 1k | ARIN | US | 26th Feb 2026 |
| 152.55.252.0/22 | 1k | ARIN | US | 28th Apr 2026 |
| 152.64.0.0/16 | 65.5k | ARIN | US | 19th Aug 1991 |
| 152.68.0.0/16 | 65.5k | ARIN | US | 21st Aug 1991 |
| 152.89.128.0/22 | 1k | RIPE NCC |  RO | 25th Jan 2019 |
| 152.89.136.0/22 | 1k | RIPE NCC |  ES | 25th Jan 2019 |
| 152.89.152.0/22 | 1k | RIPE NCC |  NL | 25th Jan 2019 |
| 152.89.156.0/22 | 1k | RIPE NCC |  PS | 25th Jan 2019 |
| 152.89.200.0/22 | 1k | RIPE NCC | NL | 28th Jan 2019 |
| 152.89.212.0/22 | 1k | RIPE NCC |  DE | 28th Jan 2019 |
| 152.89.24.0/22 | 1k | RIPE NCC |  GB | 23rd Jan 2019 |
| 152.89.40.0/22 | 1k | RIPE NCC | PS | 23rd Jan 2019 |
| 152.89.8.0/22 | 1k | RIPE NCC |  BZ | 23rd Jan 2019 |
| 152.89.88.0/22 | 1k | RIPE NCC | DE | 24th Jan 2019 |
| 152.95.0.0/16 | 65.5k | RIPE NCC |  DK | 3rd Sept 1991 |
| 153.120.222.0/23 | 512 | APNIC |  JP | 2nd Mar 2011 |
| 153.123.128.0/17 | 32.8k | APNIC | JP | 2nd Mar 2011 |
| 153.123.32.0/19 | 8.2k | APNIC | JP | 2nd Mar 2011 |
| 153.123.64.0/18 | 16.4k | APNIC | JP | 2nd Mar 2011 |
| 153.124.0.0/17 | 32.8k | APNIC | JP | 12th Mar 2011 |
| 153.124.240.0/20 | 4.1k | APNIC | JP | 12th Mar 2011 |
| 153.125.240.0/20 | 4.1k | APNIC | JP | 2nd Mar 2011 |
| 153.14.0.0/16 | 65.5k | ARIN | US | 16th Sept 1991 |
| 153.15.0.0/16 | 65.5k | RIPE NCC | US | 1st Sept 1993 |
| 153.16.0.0/16 | 65.5k | ARIN | US | 17th Sept 1991 |
| 153.17.0.0/16 | 65.5k | RIPE NCC | DE | 23rd Sept 1991 |
| 153.30.0.0/16 | 65.5k | ARIN | US | 23rd Sept 1991 |
| 153.4.0.0/16 | 65.5k | ARIN | US | 12th Sept 1991 |
| 153.40.0.0/16 | 65.5k | ARIN | US | 3rd Jan 1992 |
| 153.50.0.0/16 | 65.5k | ARIN | US | 10th Jun 1992 |
| 153.51.160.0/19 | 8.2k | RIPE NCC |  RU | 23rd Sept 1991 |
| 153.51.32.0/19 | 8.2k | RIPE NCC | RU | 23rd Sept 1991 |
| 153.51.64.0/19 | 8.2k | RIPE NCC | RU | 23rd Sept 1991 |
| 153.52.128.0/19 | 8.2k | ARIN | US | 23rd Sept 1991 |
| 153.52.224.0/19 | 8.2k | ARIN | US | 5th Jun 2026 |