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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 in United States
27,007 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 2604:1a60::/32 | 4.3B × /64 | ARIN | 1st Aug 2025 | |
| 2604:1a80::/32 | 4.3B × /64 | ARIN | 18th Sept 2012 | |
| 2604:1aa0::/32 | 4.3B × /64 | ARIN | 5th Aug 2025 | |
| 2604:1ac0::/32 | 4.3B × /64 | ARIN | 24th Feb 2017 | |
| 2604:1ae0::/32 | 4.3B × /64 | ARIN | 6th Aug 2025 | |
| 2604:1b20::/32 | 4.3B × /64 | ARIN | 6th Aug 2025 | |
| 2604:1b40::/32 | 4.3B × /64 | ARIN | 27th Feb 2017 | |
| 2604:1b60::/32 | 4.3B × /64 | ARIN | 7th Aug 2025 | |
| 2604:1b80::/32 | 4.3B × /64 | ARIN | 20th Sept 2012 | |
| 2604:1ba0::/32 | 4.3B × /64 | ARIN | 7th Aug 2025 | |
| 2604:1c00::/32 | 4.3B × /64 | ARIN | 17th Jun 2010 | |
| 2604:1c0::/32 | 4.3B × /64 | ARIN | 20th Dec 2016 | |
| 2604:1c80::/32 | 4.3B × /64 | ARIN | 20th Sept 2012 | |
| 2604:1d60::/32 | 4.3B × /64 | ARIN | 18th Aug 2025 | |
| 2604:1d80::/32 | 4.3B × /64 | ARIN | 21st Sept 2012 | |
| 2604:1de0::/32 | 4.3B × /64 | ARIN | 19th Aug 2025 | |
| 2604:1e00::/32 | 4.3B × /64 | ARIN | 21st Oct 2010 | |
| 2604:1e0::/32 | 4.3B × /64 | ARIN | 31st Jan 2025 | |
| 2604:1e20::/32 | 4.3B × /64 | ARIN | 21st Aug 2025 | |
| 2604:1e40::/32 | 4.3B × /64 | ARIN | 1st Mar 2017 | |
| 2604:1e60::/32 | 4.3B × /64 | ARIN | 23rd Aug 2025 | |
| 2604:1ea0::/32 | 4.3B × /64 | ARIN | 25th Aug 2025 | |
| 2604:1fa0::/32 | 4.3B × /64 | ARIN | 4th Sept 2025 | |
| 2604:1fc0::/32 | 4.3B × /64 | ARIN | 6th Mar 2017 | |
| 2604:20e0::/32 | 4.3B × /64 | ARIN | 18th Sept 2025 | |
| 2604:2120::/32 | 4.3B × /64 | ARIN | 19th Sept 2025 | |
| 2604:2140::/32 | 4.3B × /64 | ARIN | 7th Mar 2017 | |
| 2604:2160::/32 | 4.3B × /64 | ARIN | 22nd Sept 2025 | |
| 2604:21a0::/32 | 4.3B × /64 | ARIN | 23rd Sept 2025 | |
| 2604:21e0::/32 | 4.3B × /64 | ARIN | 24th Sept 2025 | |
| 2604:220::/32 | 4.3B × /64 | ARIN | 31st Jan 2025 | |
| 2604:2260::/32 | 4.3B × /64 | ARIN | 25th Sept 2025 | |
| 2604:22c0::/32 | 4.3B × /64 | ARIN | 10th Mar 2017 | |
| 2604:2320::/32 | 4.3B × /64 | ARIN | 29th Sept 2025 | |
| 2604:2480::/32 | 4.3B × /64 | ARIN | 12th Oct 2012 | |
| 2604:24a0::/32 | 4.3B × /64 | ARIN | 14th Oct 2025 | |
| 2604:2520::/32 | 4.3B × /64 | ARIN | 15th Oct 2025 | |
| 2604:25a0::/32 | 4.3B × /64 | ARIN | 16th Oct 2025 | |
| 2604:2660::/32 | 4.3B × /64 | ARIN | 22nd Oct 2025 | |
| 2604:2680::/32 | 4.3B × /64 | ARIN | 15th Oct 2012 | |
| 2604:2720::/32 | 4.3B × /64 | ARIN | 29th Oct 2025 | |
| 2604:2740::/32 | 4.3B × /64 | ARIN | 21st Mar 2017 | |
| 2604:2760::/32 | 4.3B × /64 | ARIN | 31st Oct 2025 | |
| 2604:2780::/32 | 4.3B × /64 | ARIN | 15th Oct 2012 | |
| 2604:27a0::/32 | 4.3B × /64 | ARIN | 3rd Nov 2025 | |
| 2604:27c0::/32 | 4.3B × /64 | ARIN | 21st Mar 2017 | |
| 2604:27e0::/32 | 4.3B × /64 | ARIN | 4th Nov 2025 | |
| 2604:2860::/32 | 4.3B × /64 | ARIN | 13th Nov 2025 | |
| 2604:28a0::/32 | 4.3B × /64 | ARIN | 14th Nov 2025 | |
| 2604:28c0::/32 | 4.3B × /64 | ARIN | 23rd Mar 2017 |