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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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 in United States
27,001 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 2606:2300::/32 | 4.3B × /64 | ARIN |  US | 6th Oct 2011 |
| 2606:2540::/32 | 4.3B × /64 | ARIN | US | 5th Feb 2021 |
| 2606:2640::/32 | 4.3B × /64 | ARIN | US | 9th Feb 2021 |
| 2606:2780::/32 | 4.3B × /64 | ARIN | US | 26th May 2015 |
| 2606:27c0::/32 | 4.3B × /64 | ARIN | US | 17th Feb 2021 |
| 2606:2840::/32 | 4.3B × /64 | ARIN | US | 18th Feb 2021 |
| 2606:2880::/32 | 4.3B × /64 | ARIN | US | 28th May 2015 |
| 2606:28c0::/32 | 4.3B × /64 | ARIN | US | 19th Feb 2021 |
| 2606:2900::/32 | 4.3B × /64 | ARIN | US | 10th Oct 2011 |
| 2606:2940::/32 | 4.3B × /64 | ARIN | US | 19th Feb 2021 |
| 2606:2a40::/32 | 4.3B × /64 | ARIN | US | 23rd Feb 2021 |
| 2606:2b40::/32 | 4.3B × /64 | ARIN | US | 4th Mar 2021 |
| 2606:2c00::/32 | 4.3B × /64 | ARIN | US | 2nd Sept 2010 |
| 2606:2d40::/32 | 4.3B × /64 | ARIN | US | 9th Mar 2021 |
| 2606:2d80::/32 | 4.3B × /64 | ARIN | US | 5th May 2026 |
| 2606:2dc0::/32 | 4.3B × /64 | ARIN | US | 9th Mar 2021 |
| 2606:2e40::/32 | 4.3B × /64 | ARIN | US | 11th Mar 2021 |
| 2606:2ec0::/32 | 4.3B × /64 | ARIN | US | 11th Mar 2021 |
| 2606:2f00::/32 | 4.3B × /64 | ARIN | US | 13th Oct 2011 |
| 2606:300::/32 | 4.3B × /64 | ARIN | US | 20th Sept 2011 |
| 2606:3040::/32 | 4.3B × /64 | ARIN | US | 15th Mar 2021 |
| 2606:30c0::/32 | 4.3B × /64 | ARIN | US | 15th Mar 2021 |
| 2606:31c0::/32 | 4.3B × /64 | ARIN | US | 17th Mar 2021 |
| 2606:3200::/32 | 4.3B × /64 | ARIN | US | 4th Feb 2011 |
| 2606:32c0::/32 | 4.3B × /64 | ARIN | US | 18th Mar 2021 |
| 2606:3480::/32 | 4.3B × /64 | ARIN | US | 22nd Jun 2015 |
| 2606:3500::/32 | 4.3B × /64 | ARIN | US | 14th Oct 2011 |
| 2606:3540::/32 | 4.3B × /64 | ARIN | US | 23rd Mar 2021 |
| 2606:35c0::/32 | 4.3B × /64 | ARIN | US | 25th Mar 2021 |
| 2606:3880::/32 | 4.3B × /64 | ARIN | US | 25th Jun 2015 |
| 2606:3940::/32 | 4.3B × /64 | ARIN | US | 30th Mar 2021 |
| 2606:3980::/36 | 268M × /64 | ARIN | US | 29th Jun 2015 |
| 2606:39c0::/32 | 4.3B × /64 | ARIN | US | 31st Mar 2021 |
| 2606:3a40::/32 | 4.3B × /64 | ARIN | US | 31st Mar 2021 |
| 2606:3ac0::/32 | 4.3B × /64 | ARIN | US | 31st Mar 2021 |
| 2606:3b40::/32 | 4.3B × /64 | ARIN | US | 1st Apr 2021 |
| 2606:3bc0::/32 | 4.3B × /64 | ARIN | US | 2nd Apr 2021 |
| 2606:3cc0::/32 | 4.3B × /64 | ARIN | US | 6th Apr 2021 |
| 2606:3e00::/32 | 4.3B × /64 | ARIN | US | 7th Feb 2011 |
| 2606:3e40::/32 | 4.3B × /64 | ARIN | US | 8th Apr 2021 |
| 2606:3e80::/32 | 4.3B × /64 | ARIN | US | 2nd Jul 2015 |
| 2606:3ec0::/32 | 4.3B × /64 | ARIN | US | 9th Apr 2021 |
| 2606:3f00::/32 | 4.3B × /64 | ARIN | US | 26th Oct 2011 |
| 2606:4000::/32 | 4.3B × /64 | ARIN | US | 25th Feb 2010 |
| 2606:4080::/32 | 4.3B × /64 | ARIN | US | 6th Jul 2015 |
| 2606:4400::/32 | 4.3B × /64 | ARIN | US | 8th Sept 2010 |
| 2606:4430::/32 | 4.3B × /64 | ARIN | US | 8th Jul 2026 |
| 2606:4490::/32 | 4.3B × /64 | ARIN | US | 8th Jul 2026 |
| 2606:4500::/32 | 4.3B × /64 | ARIN | US | 31st Oct 2011 |
| 2606:46c0::/32 | 4.3B × /64 | ARIN | US | 22nd Apr 2021 |