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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,149 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.207.219.0/24 | 256 | ARIN |  US | 11th Sept 1992 |
| 192.207.22.0/24 | 256 | ARIN | US | 13th Aug 1992 |
| 192.207.220.0/24 | 256 | ARIN | US | 11th Sept 1992 |
| 192.207.221.0/24 | 256 | ARIN | US | 11th Sept 1992 |
| 192.207.222.0/24 | 256 | ARIN | US | 11th Sept 1992 |
| 192.207.223.0/24 | 256 | ARIN | US | 15th Sept 1992 |
| 192.207.224.0/24 | 256 | ARIN | US | 15th Sept 1992 |
| 192.207.227.0/24 | 256 | ARIN | US | 15th Sept 1992 |
| 192.207.228.0/24 | 256 | ARIN | US | 15th Sept 1992 |
| 192.207.229.0/24 | 256 | ARIN | US | 21st Jul 1993 |
| 192.207.23.0/24 | 256 | ARIN | US | 13th Aug 1992 |
| 192.207.231.0/24 | 256 | ARIN | US | 21st Jul 1993 |
| 192.207.232.0/24 | 256 | ARIN | US | 15th Sept 1992 |
| 192.207.233.0/24 | 256 | ARIN | US | 15th Sept 1992 |
| 192.207.235.0/24 | 256 | ARIN | US | 15th Sept 1992 |
| 192.207.237.0/24 | 256 | ARIN | US | 5th Dec 2022 |
| 192.207.239.0/24 | 256 | ARIN | US | 16th Sept 1992 |
| 192.207.24.0/24 | 256 | ARIN | US | 13th Aug 1992 |
| 192.207.243.0/24 | 256 | ARIN | US | 17th Sept 1992 |
| 192.207.245.0/24 | 256 | ARIN | US | 17th Sept 1992 |
| 192.207.249.0/24 | 256 | ARIN | US | 18th Sept 1992 |
| 192.207.250.0/24 | 256 | ARIN | US | 18th Sept 1992 |
| 192.207.251.0/24 | 256 | ARIN | US | 18th Sept 1992 |
| 192.207.253.0/24 | 256 | ARIN | US | 18th Sept 1992 |
| 192.207.254.0/24 | 256 | APNIC |  ID | 23rd Jan 2026 |
| 192.207.26.0/24 | 256 | ARIN | US | 2nd Apr 2026 |
| 192.207.27.0/24 | 256 | ARIN | US | 17th Aug 1992 |
| 192.207.28.0/24 | 256 | ARIN | US | 17th Aug 1992 |
| 192.207.29.0/24 | 256 | ARIN | US | 17th Aug 1992 |
| 192.207.30.0/24 | 256 | ARIN | US | 17th Aug 1992 |
| 192.207.31.0/24 | 256 | RIPE NCC |  NL | 18th Aug 1992 |
| 192.207.32.0/24 | 256 | ARIN | US | 18th Aug 1992 |
| 192.207.33.0/24 | 256 | APNIC |  AU | 18th Aug 1992 |
| 192.207.34.0/23 | 512 | ARIN | US | 24th Apr 2015 |
| 192.207.37.0/24 | 256 | ARIN | US | 18th Aug 1992 |
| 192.207.38.0/23 | 512 | ARIN | US | 18th Aug 1992 |
| 192.207.4.0/22 | 1k | ARIN | US | 12th Aug 1992 |
| 192.207.40.0/24 | 256 | LACNIC |  EC | 18th Aug 1992 |
| 192.207.41.0/24 | 256 | LACNIC | EC | 18th Aug 1992 |
| 192.207.42.0/24 | 256 | LACNIC | EC | 18th Aug 1992 |
| 192.207.43.0/24 | 256 | ARIN | US | 18th Aug 1992 |
| 192.207.44.0/24 | 256 | ARIN | US | 18th Aug 1992 |
| 192.207.47.0/24 | 256 | RIPE NCC |  IL | 18th Aug 1992 |
| 192.207.48.0/24 | 256 | ARIN |  PR | 12th Jul 1994 |
| 192.207.49.0/24 | 256 | ARIN | US | 24th Jul 2015 |
| 192.207.50.0/24 | 256 | ARIN | US | 19th Aug 1992 |
| 192.207.51.0/24 | 256 | ARIN | US | 19th Aug 1992 |
| 192.207.52.0/23 | 512 | ARIN | US | 19th Aug 1992 |
| 192.207.54.0/24 | 256 | ARIN | US | 19th Aug 1992 |
| 192.207.60.0/23 | 512 | ARIN |  CA | 23rd Aug 2024 |