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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 unannounced space registered through ARIN, largest first.
Unannounced blocks registered through ARIN
30,418 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 129.230.128.0/19 | 8.2k | ARIN |  US | 10th Mar 1988 |
| 129.230.160.0/20 | 4.1k | ARIN | US | 10th Mar 1988 |
| 129.231.0.0/16 | 65.5k | ARIN | US | 11th Mar 1988 |
| 129.243.0.0/16 | 65.5k | ARIN | US | 3rd Jun 1997 |
| 129.245.0.0/16 | 65.5k | ARIN | US | 29th Mar 1988 |
| 129.248.0.0/16 | 65.5k | ARIN | US | 1st Apr 1988 |
| 129.253.64.0/18 | 16.4k | ARIN | US | 8th Apr 1988 |
| 129.33.128.0/21 | 2k | ARIN | US | 22nd Jun 1989 |
| 129.33.136.0/23 | 512 | ARIN | US | 22nd Jun 1989 |
| 129.33.144.0/20 | 4.1k | ARIN | US | 22nd Jun 1989 |
| 129.33.232.0/22 | 1k | ARIN | US | 22nd Jun 1989 |
| 129.33.236.0/23 | 512 | ARIN | US | 22nd Jun 1989 |
| 129.33.238.0/24 | 256 | ARIN | US | 22nd Jun 1989 |
| 129.33.241.0/24 | 256 | ARIN | US | 22nd Jun 1989 |
| 129.33.242.0/24 | 256 | ARIN | US | 22nd Jun 1989 |
| 129.33.244.0/22 | 1k | ARIN | US | 22nd Jun 1989 |
| 129.33.248.0/21 | 2k | ARIN | US | 22nd Jun 1989 |
| 129.38.0.0/16 | 65.5k | ARIN | US | 25th Nov 2024 |
| 129.40.0.0/16 | 65.5k | ARIN | US | 6th Jun 1989 |
| 129.41.112.0/20 | 4.1k | ARIN | US | 29th Jul 1987 |
| 129.41.160.0/22 | 1k | ARIN | US | 29th Jul 1987 |
| 129.41.164.0/23 | 512 | ARIN | US | 29th Jul 1987 |
| 129.41.176.0/24 | 256 | ARIN | US | 29th Jul 1987 |
| 129.41.177.0/24 | 256 | ARIN | US | 29th Jul 1987 |
| 129.41.180.0/22 | 1k | ARIN | US | 29th Jul 1987 |
| 129.41.184.0/22 | 1k | ARIN | US | 29th Jul 1987 |
| 129.41.188.0/23 | 512 | ARIN | US | 29th Jul 1987 |
| 129.41.190.0/23 | 512 | ARIN | US | 29th Jul 1987 |
| 129.41.208.0/23 | 512 | ARIN | US | 29th Jul 1987 |
| 129.41.210.0/23 | 512 | ARIN | US | 29th Jul 1987 |
| 129.41.212.0/22 | 1k | ARIN | US | 29th Jul 1987 |
| 129.41.217.0/24 | 256 | ARIN | US | 29th Jul 1987 |
| 129.41.218.0/23 | 512 | ARIN | US | 29th Jul 1987 |
| 129.41.223.0/24 | 256 | ARIN | US | 29th Jul 1987 |
| 129.41.36.0/22 | 1k | ARIN | US | 29th Jul 1987 |
| 129.41.42.0/24 | 256 | ARIN | US | 29th Jul 1987 |
| 129.41.43.0/24 | 256 | ARIN | US | 29th Jul 1987 |
| 129.41.44.0/24 | 256 | ARIN | US | 29th Jul 1987 |
| 129.41.48.0/22 | 1k | ARIN | US | 29th Jul 1987 |
| 129.41.54.0/23 | 512 | ARIN | US | 29th Jul 1987 |
| 129.41.60.0/23 | 512 | ARIN | US | 29th Jul 1987 |
| 129.41.64.0/21 | 2k | ARIN | US | 29th Jul 1987 |
| 129.41.80.0/22 | 1k | ARIN | US | 29th Jul 1987 |
| 129.41.92.0/23 | 512 | ARIN | US | 29th Jul 1987 |
| 129.41.94.0/24 | 256 | ARIN | US | 29th Jul 1987 |
| 129.41.96.0/20 | 4.1k | ARIN | US | 29th Jul 1987 |
| 129.50.0.0/16 | 65.5k | ARIN | US | 5th Aug 1987 |
| 129.58.0.0/16 | 65.5k | ARIN | US | 7th Aug 1987 |
| 129.75.0.0/16 | 65.5k | ARIN | US | 19th Nov 2014 |
| 129.76.0.0/16 | 65.5k | ARIN | US | 25th Sept 1987 |