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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 138.252.36.0/23 | 512 | APNIC |  IN | 11th Oct 2025 |
| 138.252.42.0/24 | 256 | APNIC | IN | 14th Oct 2025 |
| 138.252.50.0/24 | 256 | APNIC |  ID | 16th Oct 2025 |
| 138.252.60.0/23 | 512 | APNIC |  HK | 17th Oct 2025 |
| 138.252.70.0/24 | 256 | APNIC | ID | 20th Oct 2025 |
| 138.252.78.0/23 | 512 | APNIC |  CN | 21st Oct 2025 |
| 138.31.0.0/16 | 65.5k | ARIN |  US | 31st Jan 1990 |
| 138.32.128.0/19 | 8.2k | ARIN | US | 31st Jan 1990 |
| 138.32.160.0/21 | 2k | ARIN | US | 31st Jan 1990 |
| 138.32.172.0/22 | 1k | ARIN | US | 31st Jan 1990 |
| 138.32.176.0/20 | 4.1k | ARIN | US | 31st Jan 1990 |
| 138.32.28.0/22 | 1k | ARIN | US | 31st Jan 1990 |
| 138.35.0.0/16 | 65.5k | ARIN | US | 31st Jan 1990 |
| 138.36.146.0/24 | 256 | LACNIC |  VE | 28th Jan 2015 |
| 138.39.0.0/16 | 65.5k | ARIN | US | 31st Jan 1990 |
| 138.42.0.0/16 | 65.5k | ARIN | US | 31st Jan 1990 |
| 138.43.192.0/20 | 4.1k | APNIC | HK | 31st Jan 1990 |
| 138.53.0.0/16 | 65.5k | ARIN | US | 7th Feb 1990 |
| 138.54.0.0/15 | 131k | ARIN | US | 7th Feb 1990 |
| 138.59.108.0/22 | 1k | LACNIC |  EC | 10th Mar 2015 |
| 138.59.116.0/22 | 1k | LACNIC | VE | 13th Feb 2015 |
| 138.76.0.0/16 | 65.5k | ARIN | US | 2nd Mar 1990 |
| 138.82.0.0/16 | 65.5k | ARIN |  CA | 9th Mar 1990 |
| 138.84.200.0/24 | 256 | ARIN | US | 9th Mar 1990 |
| 138.84.202.0/24 | 256 | ARIN | US | 9th Mar 1990 |
| 138.93.0.0/16 | 65.5k | ARIN | US | 19th Apr 1990 |
| 138.94.248.0/22 | 1k | LACNIC |  GY | 6th Apr 2015 |
| 138.95.0.0/16 | 65.5k | ARIN | US | 20th Apr 1990 |
| 138.97.172.0/22 | 1k | LACNIC |  BR | 30th Mar 2015 |
| 138.99.24.0/22 | 1k | LACNIC | BR | 13th Mar 2015 |
| 139.10.0.0/16 | 65.5k | RIPE NCC |  DE | 1st Sept 1993 |
| 139.100.0.0/23 | 512 | RIPE NCC |  UA | 15th Feb 1990 |
| 139.100.100.0/22 | 1k | RIPE NCC | US | 15th Feb 1990 |
| 139.100.112.0/20 | 4.1k | RIPE NCC | US | 15th Feb 1990 |
| 139.100.16.0/23 | 512 | RIPE NCC | UA | 15th Feb 1990 |
| 139.100.160.0/20 | 4.1k | RIPE NCC |  RU | 15th Feb 1990 |
| 139.100.18.0/23 | 512 | RIPE NCC |  FR | 15th Feb 1990 |
| 139.100.184.0/21 | 2k | RIPE NCC | FR | 15th Feb 1990 |
| 139.100.20.0/22 | 1k | RIPE NCC | FR | 15th Feb 1990 |
| 139.100.24.0/21 | 2k | RIPE NCC | FR | 15th Feb 1990 |
| 139.100.6.0/23 | 512 | RIPE NCC | FR | 15th Feb 1990 |
| 139.100.8.0/21 | 2k | RIPE NCC | FR | 15th Feb 1990 |
| 139.100.96.0/23 | 512 | RIPE NCC |  CR | 15th Feb 1990 |
| 139.100.98.0/24 | 256 | RIPE NCC | FR | 15th Feb 1990 |
| 139.100.99.0/24 | 256 | RIPE NCC | US | 15th Feb 1990 |
| 139.136.0.0/16 | 65.5k | ARIN | US | 14th Mar 1990 |
| 139.150.96.0/19 | 8.2k | APNIC |  KR | 9th Mar 2011 |
| 139.154.0.0/16 | 65.5k | APNIC |  JP | 7th Feb 1996 |
| 139.156.0.0/16 | 65.5k | RIPE NCC |  NL | 1st Sept 1993 |
| 139.158.0.0/16 | 65.5k | RIPE NCC | FR | 1st Sept 1993 |