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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,310 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 199.96.156.0/22 | 1k | ARIN |  US | 16th Feb 2011 |
| 199.96.160.0/22 | 1k | ARIN | US | 16th Feb 2011 |
| 199.96.172.0/22 | 1k | ARIN | US | 18th Feb 2011 |
| 2.0.0.0/15 | 131k | RIPE NCC |  SE | 12th Jul 2010 |
| 2.152.128.0/19 | 8.2k | RIPE NCC |  ES | 3rd Nov 2010 |
| 2.152.16.0/20 | 4.1k | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.160.0/20 | 4.1k | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.180.0/23 | 512 | RIPE NCC |  FR | 3rd Nov 2010 |
| 2.152.182.0/23 | 512 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.184.0/21 | 2k | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.192.0/20 | 4.1k | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.208.0/22 | 1k | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.224.0/20 | 4.1k | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.240.0/22 | 1k | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.244.0/23 | 512 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.247.0/24 | 256 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.248.0/23 | 512 | LACNIC |  PY | 3rd Aug 2026 |
| 2.152.250.0/24 | 256 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.251.0/24 | 256 | LACNIC |  VE | 24th Aug 2026 |
| 2.152.252.0/22 | 1k | LACNIC |  PA | 26th Aug 2026 |
| 2.152.32.0/24 | 256 | LACNIC |  DO | 24th Aug 2026 |
| 2.152.34.0/23 | 512 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.36.0/22 | 1k | LACNIC |  EC | 26th Aug 2026 |
| 2.152.40.0/23 | 512 | LACNIC |  GT | 20th Jul 2026 |
| 2.152.42.0/23 | 512 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.44.0/23 | 512 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.46.0/24 | 256 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.47.0/24 | 256 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.48.0/21 | 2k | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.56.0/23 | 512 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.58.0/23 | 512 | LACNIC | DO | 24th Aug 2026 |
| 2.152.6.0/23 | 512 | LACNIC | DO | 24th Aug 2026 |
| 2.152.60.0/22 | 1k | LACNIC | DO | 24th Aug 2026 |
| 2.152.64.0/23 | 512 | RIPE NCC |  DE | 3rd Nov 2010 |
| 2.152.72.0/24 | 256 | RIPE NCC |  MT | 3rd Nov 2010 |
| 2.152.73.0/24 | 256 | RIPE NCC |  GB | 3rd Nov 2010 |
| 2.152.75.0/24 | 256 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.76.0/23 | 512 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.78.0/24 | 256 | RIPE NCC |  EE | 3rd Nov 2010 |
| 2.152.79.0/24 | 256 | RIPE NCC | DE | 3rd Nov 2010 |
| 2.152.80.0/21 | 2k | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.88.0/24 | 256 | RIPE NCC |  BG | 3rd Nov 2010 |
| 2.152.89.0/24 | 256 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.90.0/23 | 512 | RIPE NCC | ES | 3rd Nov 2010 |
| 2.152.92.0/23 | 512 | RIPE NCC | BG | 3rd Nov 2010 |
| 2.152.94.0/23 | 512 | RIPE NCC | DE | 3rd Nov 2010 |
| 2.152.96.0/19 | 8.2k | RIPE NCC | ES | 3rd Nov 2010 |
| 2.2.0.0/16 | 65.5k | RIPE NCC | SE | 12th Jul 2010 |
| 2.252.0.0/15 | 131k | RIPE NCC | SE | 30th Dec 2010 |
| 2.254.0.0/16 | 65.5k | RIPE NCC | SE | 30th Dec 2010 |