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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,248 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 198.17.12.0/24 | 256 | ARIN |  US | 3rd Dec 1992 |
| 198.17.122.0/24 | 256 | ARIN | US | 23rd Dec 1992 |
| 198.17.123.0/24 | 256 | ARIN | US | 23rd Dec 1992 |
| 198.17.125.0/24 | 256 | ARIN | US | 23rd Dec 1992 |
| 198.17.129.0/24 | 256 | ARIN | US | 23rd Dec 1992 |
| 198.17.134.0/24 | 256 | ARIN | US | 28th Dec 1992 |
| 198.17.135.0/24 | 256 | ARIN | US | 29th Dec 1992 |
| 198.17.136.0/24 | 256 | ARIN | US | 29th Dec 1992 |
| 198.17.137.0/24 | 256 | ARIN | US | 29th Dec 1992 |
| 198.17.138.0/24 | 256 | ARIN | US | 29th Dec 1992 |
| 198.17.140.0/24 | 256 | ARIN |  CA | 29th Dec 1992 |
| 198.17.141.0/24 | 256 | ARIN | US | 29th Dec 1992 |
| 198.17.142.0/24 | 256 | ARIN | US | 29th Dec 1992 |
| 198.17.143.0/24 | 256 | ARIN | US | 30th Dec 1992 |
| 198.17.146.0/24 | 256 | ARIN | US | 30th Dec 1992 |
| 198.17.148.0/24 | 256 | ARIN | US | 30th Dec 1992 |
| 198.17.149.0/24 | 256 | ARIN | US | 30th Dec 1992 |
| 198.17.150.0/24 | 256 | ARIN | US | 30th Dec 1992 |
| 198.17.151.0/24 | 256 | ARIN | US | 30th Dec 1992 |
| 198.17.152.0/24 | 256 | ARIN | US | 30th Dec 1992 |
| 198.17.153.0/24 | 256 | ARIN | US | 30th Dec 1992 |
| 198.17.157.0/24 | 256 | ARIN | US | 8th Jan 1993 |
| 198.17.158.0/24 | 256 | ARIN | US | 2nd Jul 2026 |
| 198.17.159.0/24 | 256 | ARIN | US | 7th Jul 2026 |
| 198.17.16.0/24 | 256 | ARIN | US | 3rd Dec 1992 |
| 198.17.161.0/24 | 256 | ARIN | US | 11th Jan 1993 |
| 198.17.162.0/24 | 256 | ARIN | US | 11th Jan 1993 |
| 198.17.163.0/24 | 256 | ARIN | US | 11th Jan 1993 |
| 198.17.165.0/24 | 256 | ARIN | US | 11th Jan 1993 |
| 198.17.166.0/24 | 256 | ARIN | US | 11th Jan 1993 |
| 198.17.167.0/24 | 256 | ARIN | US | 11th Jan 1993 |
| 198.17.17.0/24 | 256 | ARIN | US | 3rd Dec 1992 |
| 198.17.172.0/24 | 256 | ARIN | US | 12th Jan 1993 |
| 198.17.173.0/24 | 256 | ARIN | US | 12th Jan 1993 |
| 198.17.174.0/24 | 256 | ARIN | US | 12th Jan 1993 |
| 198.17.176.0/24 | 256 | ARIN | US | 12th Jan 1993 |
| 198.17.177.0/24 | 256 | ARIN | US | 12th Jan 1993 |
| 198.17.178.0/24 | 256 | ARIN | US | 25th Apr 2013 |
| 198.17.18.0/24 | 256 | ARIN | US | 3rd Dec 1992 |
| 198.17.180.0/24 | 256 | RIPE NCC |  NL | 12th Jan 1993 |
| 198.17.181.0/24 | 256 | RIPE NCC | NL | 12th Jan 1993 |
| 198.17.182.0/24 | 256 | RIPE NCC | NL | 12th Jan 1993 |
| 198.17.197.0/24 | 256 | ARIN | US | 13th Jan 1993 |
| 198.17.198.0/24 | 256 | ARIN | US | 13th Jan 1993 |
| 198.17.2.0/24 | 256 | ARIN | US | 1st Dec 1992 |
| 198.17.20.0/22 | 1k | ARIN | US | 31st Oct 2012 |
| 198.17.202.0/24 | 256 | ARIN | US | 13th Jan 1993 |
| 198.17.203.0/24 | 256 | ARIN | US | 13th Jan 1993 |
| 198.17.204.0/24 | 256 | ARIN | US | 13th Jan 1993 |
| 198.17.205.0/24 | 256 | ARIN | US | 14th Jan 1993 |