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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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.
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Countries with the most unannounced blocks, largest first.
Unannounced blocks
85,279 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 2604:1820::/32 | 4.3B × /64 | ARIN |  US | 23rd Jul 2025 |
| 2604:1860::/32 | 4.3B × /64 | ARIN |  CA | 24th Jul 2025 |
| 2604:1880::/32 | 4.3B × /64 | ARIN | US | 6th Sept 2012 |
| 2604:18a0::/32 | 4.3B × /64 | ARIN | CA | 24th Jul 2025 |
| 2604:18e0::/32 | 4.3B × /64 | ARIN | CA | 24th Jul 2025 |
| 2604:1920::/32 | 4.3B × /64 | ARIN | CA | 24th Jul 2025 |
| 2604:19c0::/32 | 4.3B × /64 | ARIN | US | 24th Feb 2017 |
| 2604:19e0::/32 | 4.3B × /64 | ARIN | US | 30th Jul 2025 |
| 2604:1a40::/32 | 4.3B × /64 | ARIN | US | 24th Feb 2017 |
| 2604:1a60::/32 | 4.3B × /64 | ARIN | US | 1st Aug 2025 |
| 2604:1a80::/32 | 4.3B × /64 | ARIN | US | 18th Sept 2012 |
| 2604:1aa0::/32 | 4.3B × /64 | ARIN | US | 5th Aug 2025 |
| 2604:1ac0::/32 | 4.3B × /64 | ARIN | US | 24th Feb 2017 |
| 2604:1ae0::/32 | 4.3B × /64 | ARIN | US | 6th Aug 2025 |
| 2604:1b00::/32 | 4.3B × /64 | ARIN | CA | 24th Mar 2011 |
| 2604:1b20::/32 | 4.3B × /64 | ARIN | US | 6th Aug 2025 |
| 2604:1b40::/32 | 4.3B × /64 | ARIN | US | 27th Feb 2017 |
| 2604:1b60::/32 | 4.3B × /64 | ARIN | US | 7th Aug 2025 |
| 2604:1b80::/32 | 4.3B × /64 | ARIN | US | 20th Sept 2012 |
| 2604:1ba0::/32 | 4.3B × /64 | ARIN | US | 7th Aug 2025 |
| 2604:1c00::/32 | 4.3B × /64 | ARIN | US | 17th Jun 2010 |
| 2604:1c0::/32 | 4.3B × /64 | ARIN | US | 20th Dec 2016 |
| 2604:1c80::/32 | 4.3B × /64 | ARIN | US | 20th Sept 2012 |
| 2604:1d00::/32 | 4.3B × /64 | ARIN | CA | 25th Mar 2011 |
| 2604:1d60::/32 | 4.3B × /64 | ARIN | US | 18th Aug 2025 |
| 2604:1d80::/32 | 4.3B × /64 | ARIN | US | 21st Sept 2012 |
| 2604:1da0::/32 | 4.3B × /64 | ARIN |  PR | 19th Aug 2025 |
| 2604:1de0::/32 | 4.3B × /64 | ARIN | US | 19th Aug 2025 |
| 2604:1e00::/32 | 4.3B × /64 | ARIN | US | 21st Oct 2010 |
| 2604:1e0::/32 | 4.3B × /64 | ARIN | US | 31st Jan 2025 |
| 2604:1e20::/32 | 4.3B × /64 | ARIN | US | 21st Aug 2025 |
| 2604:1e40::/32 | 4.3B × /64 | ARIN | US | 1st Mar 2017 |
| 2604:1e60::/32 | 4.3B × /64 | ARIN | US | 23rd Aug 2025 |
| 2604:1e80::/32 | 4.3B × /64 | ARIN | CA | 24th Sept 2012 |
| 2604:1ea0::/32 | 4.3B × /64 | ARIN | US | 25th Aug 2025 |
| 2604:1fa0::/32 | 4.3B × /64 | ARIN | US | 4th Sept 2025 |
| 2604:1fc0::/32 | 4.3B × /64 | ARIN | US | 6th Mar 2017 |
| 2604:20e0::/32 | 4.3B × /64 | ARIN | US | 18th Sept 2025 |
| 2604:2120::/32 | 4.3B × /64 | ARIN | US | 19th Sept 2025 |
| 2604:2140::/32 | 4.3B × /64 | ARIN | US | 7th Mar 2017 |
| 2604:2160::/32 | 4.3B × /64 | ARIN | US | 22nd Sept 2025 |
| 2604:21a0::/32 | 4.3B × /64 | ARIN | US | 23rd Sept 2025 |
| 2604:21e0::/32 | 4.3B × /64 | ARIN | US | 24th Sept 2025 |
| 2604:220::/32 | 4.3B × /64 | ARIN | US | 31st Jan 2025 |
| 2604:2260::/32 | 4.3B × /64 | ARIN | US | 25th Sept 2025 |
| 2604:22c0::/32 | 4.3B × /64 | ARIN | US | 10th Mar 2017 |
| 2604:2320::/32 | 4.3B × /64 | ARIN | US | 29th Sept 2025 |
| 2604:23c0::/32 | 4.3B × /64 | ARIN | CA | 16th Mar 2017 |
| 2604:2460::/32 | 4.3B × /64 | ARIN | CA | 7th Oct 2025 |
| 2604:2480::/32 | 4.3B × /64 | ARIN | US | 12th Oct 2012 |