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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
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Countries with the most unannounced blocks, largest first.
Unannounced blocks
84,960 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 128.152.0.0/16 | 65.5k | ARIN |  US | 9th Sept 1986 |
| 128.161.0.0/16 | 65.5k | ARIN | US | 24th Sept 1986 |
| 128.162.0.0/16 | 65.5k | ARIN | US | 24th Sept 1986 |
| 128.166.0.0/16 | 65.5k | ARIN | US | 29th Sept 1986 |
| 128.20.0.0/16 | 65.5k | ARIN | US | 12th May 1983 |
| 128.204.193.0/24 | 256 | RIPE NCC |  NL | 13th Oct 2011 |
| 128.204.194.0/24 | 256 | RIPE NCC | NL | 13th Oct 2011 |
| 128.204.195.0/24 | 256 | RIPE NCC | NL | 13th Oct 2011 |
| 128.204.196.0/23 | 512 | RIPE NCC | NL | 13th Oct 2011 |
| 128.204.198.0/24 | 256 | RIPE NCC | NL | 13th Oct 2011 |
| 128.204.199.0/24 | 256 | RIPE NCC | NL | 13th Oct 2011 |
| 128.204.200.0/21 | 2k | RIPE NCC | NL | 13th Oct 2011 |
| 128.204.224.0/20 | 4.1k | RIPE NCC |  FR | 13th Oct 2011 |
| 128.207.0.0/16 | 65.5k | ARIN | US | 5th Mar 1987 |
| 128.209.0.0/16 | 65.5k | ARIN | US | 14th Apr 2000 |
| 128.215.0.0/16 | 65.5k | ARIN | US | 16th Mar 1987 |
| 128.222.0.0/16 | 65.5k | ARIN | US | 24th Mar 1987 |
| 128.225.0.0/16 | 65.5k | ARIN | US | 7th Apr 1987 |
| 128.247.0.0/16 | 65.5k | ARIN | US | 28th May 1987 |
| 128.254.0.0/17 | 32.8k | ARIN | US | 4th Jun 1987 |
| 128.254.152.0/22 | 1k | ARIN | US | 1st Jul 2026 |
| 128.254.196.0/22 | 1k | ARIN |  CA | 4th Oct 2022 |
| 128.254.212.0/22 | 1k | ARIN | US | 3rd Oct 2022 |
| 128.254.228.0/22 | 1k | ARIN | US | 3rd Oct 2022 |
| 128.45.0.0/16 | 65.5k | RIPE NCC |  IT | 6th Oct 2011 |
| 128.50.0.0/16 | 65.5k | ARIN | US | 13th Mar 1984 |
| 128.51.0.0/16 | 65.5k | ARIN | US | 13th Mar 1984 |
| 128.66.0.0/15 | 131k | RIPE NCC | IT | 6th Oct 2011 |
| 128.76.64.0/18 | 16.4k | RIPE NCC |  SE | 14th Nov 2011 |
| 128.88.0.0/16 | 65.5k | ARIN | US | 17th Jul 1985 |
| 128.89.0.0/16 | 65.5k | ARIN | US | 28th Oct 2022 |
| 128.99.0.0/16 | 65.5k | ARIN | US | 9th Jan 1986 |
| 129.101.64.0/20 | 4.1k | RIPE NCC |  RU | 13th Jun 1988 |
| 129.101.96.0/19 | 8.2k | RIPE NCC | US | 13th Jun 1988 |
| 129.103.0.0/16 | 65.5k | RIPE NCC |  DE | 12th Nov 1987 |
| 129.124.0.0/16 | 65.5k | ARIN | US | 1st Dec 1987 |
| 129.133.192.0/19 | 8.2k | ARIN | US | 19th Jul 2024 |
| 129.136.0.0/16 | 65.5k | APNIC |  JP | 11th Dec 1987 |
| 129.14.0.0/16 | 65.5k | ARIN | US | 29th Jun 1987 |
| 129.167.0.0/16 | 65.5k | ARIN | US | 4th Jan 1988 |
| 129.172.0.0/16 | 65.5k | ARIN | US | 12th Jan 1988 |
| 129.179.0.0/16 | 65.5k | ARIN | US | 18th Jan 1988 |
| 129.193.0.0/16 | 65.5k | ARIN | US | 5th Feb 1988 |
| 129.197.0.0/16 | 65.5k | ARIN | US | 7th Jul 1997 |
| 129.200.0.0/16 | 65.5k | ARIN | US | 12th Feb 1988 |
| 129.201.0.0/16 | 65.5k | ARIN | US | 16th Feb 1988 |
| 129.202.0.0/16 | 65.5k | ARIN | US | 16th Feb 1988 |
| 129.203.0.0/16 | 65.5k | ARIN | US | 29th Dec 2022 |
| 129.214.0.0/16 | 65.5k | RIPE NCC | DE | 1st Sept 1993 |
| 129.216.0.0/16 | 65.5k | ARIN | US | 1st Mar 1988 |