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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 |
|---|---|---|---|---|
| 157.212.0.0/16 | 65.5k | ARIN |  US | 15th Jun 2022 |
| 157.22.152.0/22 | 1k | RIPE NCC |  RU | 14th Oct 1997 |
| 157.22.160.0/22 | 1k | RIPE NCC | RU | 14th Oct 1997 |
| 157.22.164.0/22 | 1k | RIPE NCC | RU | 14th Oct 1997 |
| 157.22.168.0/22 | 1k | RIPE NCC | RU | 14th Oct 1997 |
| 157.22.208.0/21 | 2k | RIPE NCC |  UZ | 14th Oct 1997 |
| 157.22.216.0/22 | 1k | RIPE NCC | RU | 14th Oct 1997 |
| 157.22.220.0/23 | 512 | RIPE NCC | RU | 14th Oct 1997 |
| 157.22.228.0/24 | 256 | RIPE NCC | RU | 14th Oct 1997 |
| 157.22.244.0/22 | 1k | RIPE NCC | RU | 14th Oct 1997 |
| 157.22.248.0/22 | 1k | RIPE NCC | RU | 14th Oct 1997 |
| 157.22.254.0/24 | 256 | RIPE NCC | RU | 14th Oct 1997 |
| 157.22.255.0/24 | 256 | RIPE NCC |  SC | 14th Oct 1997 |
| 157.226.0.0/16 | 65.5k | ARIN | US | 30th Jan 1992 |
| 157.227.0.0/16 | 65.5k | APNIC |  AU | 23rd Mar 1992 |
| 157.228.100.0/22 | 1k | RIPE NCC |  AM | 7th Apr 2004 |
| 157.228.104.0/21 | 2k | RIPE NCC | AM | 7th Apr 2004 |
| 157.228.112.0/20 | 4.1k | RIPE NCC |  AE | 7th Apr 2004 |
| 157.228.192.0/18 | 16.4k | RIPE NCC |  NL | 7th Apr 2004 |
| 157.228.32.0/19 | 8.2k | RIPE NCC |  GB | 7th Apr 2004 |
| 157.228.64.0/19 | 8.2k | RIPE NCC | AM | 7th Apr 2004 |
| 157.228.96.0/24 | 256 | RIPE NCC | RU | 7th Apr 2004 |
| 157.228.97.0/24 | 256 | RIPE NCC | AM | 7th Apr 2004 |
| 157.228.98.0/23 | 512 | RIPE NCC | AM | 7th Apr 2004 |
| 157.239.130.0/23 | 512 | ARIN | US | 4th Feb 1992 |
| 157.239.132.0/22 | 1k | ARIN | US | 4th Feb 1992 |
| 157.239.136.0/21 | 2k | ARIN | US | 4th Feb 1992 |
| 157.239.144.0/20 | 4.1k | ARIN | US | 4th Feb 1992 |
| 157.239.160.0/19 | 8.2k | ARIN | US | 4th Feb 1992 |
| 157.250.128.0/19 | 8.2k | APNIC |  JP | 7th Feb 1992 |
| 157.250.176.0/20 | 4.1k | APNIC | JP | 7th Feb 1992 |
| 157.250.208.0/20 | 4.1k | APNIC | JP | 7th Feb 1992 |
| 157.251.0.0/16 | 65.5k | ARIN | US | 7th Feb 1992 |
| 157.5.64.0/18 | 16.4k | ARIN | US | 12th Mar 2024 |
| 157.66.10.0/23 | 512 | APNIC |  VN | 25th Mar 2024 |
| 157.66.110.0/23 | 512 | APNIC |  IN | 16th Apr 2024 |
| 157.66.112.0/23 | 512 | APNIC |  ID | 16th Apr 2024 |
| 157.66.114.0/23 | 512 | APNIC | ID | 16th Apr 2024 |
| 157.66.116.0/23 | 512 | APNIC | ID | 16th Apr 2024 |
| 157.66.126.0/23 | 512 | APNIC | ID | 17th Apr 2024 |
| 157.66.130.0/24 | 256 | APNIC | ID | 17th Apr 2024 |
| 157.66.132.0/23 | 512 | APNIC | ID | 17th Apr 2024 |
| 157.66.136.0/23 | 512 | APNIC | ID | 17th Apr 2024 |
| 157.66.148.0/23 | 512 | APNIC | IN | 19th Apr 2024 |
| 157.66.168.0/23 | 512 | APNIC | ID | 25th Apr 2024 |
| 157.66.182.0/23 | 512 | APNIC | JP | 30th Apr 2024 |
| 157.66.200.0/23 | 512 | APNIC | ID | 2nd May 2024 |
| 157.66.202.0/23 | 512 | APNIC | ID | 2nd May 2024 |
| 157.66.204.0/23 | 512 | APNIC | ID | 3rd May 2024 |
| 157.66.206.0/23 | 512 | APNIC | ID | 3rd May 2024 |