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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
84,459 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 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 |
| 2606:3ec0::/32 | 4.3B × /64 | ARIN | US | 9th Apr 2021 |
| 2606:3f00::/32 | 4.3B × /64 | ARIN | US | 26th Oct 2011 |
| 2606:3f40::/32 | 4.3B × /64 | ARIN | US | 12th Apr 2021 |
| 2606:4000::/32 | 4.3B × /64 | ARIN | US | 25th Feb 2010 |
| 2606:4080::/32 | 4.3B × /64 | ARIN | US | 6th Jul 2015 |
| 2606:4140::/32 | 4.3B × /64 | ARIN |  PR | 12th Apr 2021 |
| 2606:4380::/32 | 4.3B × /64 | ARIN |  CA | 8th Jul 2015 |
| 2606:4400::/32 | 4.3B × /64 | ARIN | US | 8th Sept 2010 |
| 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 |
| 2606:47c0::/32 | 4.3B × /64 | ARIN | US | 23rd Apr 2021 |
| 2606:480::/32 | 4.3B × /64 | ARIN |  BM | 4th Mar 2015 |
| 2606:48c0::/32 | 4.3B × /64 | ARIN | US | 27th Apr 2021 |
| 2606:4940::/32 | 4.3B × /64 | ARIN | US | 27th Apr 2021 |
| 2606:4980::/32 | 4.3B × /64 | ARIN | US | 13th Jul 2015 |
| 2606:49c0::/32 | 4.3B × /64 | ARIN | CA | 7th May 2026 |
| 2606:4a40::/32 | 4.3B × /64 | ARIN | US | 28th Apr 2021 |
| 2606:4a80::/32 | 4.3B × /64 | ARIN | US | 13th Jul 2015 |
| 2606:4ac0::/32 | 4.3B × /64 | ARIN | CA | 29th Apr 2021 |
| 2606:4b80::/32 | 4.3B × /64 | ARIN | US | 14th Jul 2015 |
| 2606:4c00::/33 | 2.1B × /64 | ARIN | US | 9th Sept 2010 |
| 2606:4c0::/32 | 4.3B × /64 | ARIN | US | 28th Oct 2020 |
| 2606:4e40::/32 | 4.3B × /64 | ARIN | US | 10th May 2021 |
| 2606:4ec0::/32 | 4.3B × /64 | ARIN | US | 11th May 2021 |
| 2606:500::/32 | 4.3B × /64 | ARIN | US | 20th Sept 2011 |
| 2606:5140::/32 | 4.3B × /64 | ARIN | US | 20th May 2021 |
| 2606:5180::/32 | 4.3B × /64 | ARIN | US | 8th May 2026 |
| 2606:51c0::/32 | 4.3B × /64 | ARIN | US | 21st May 2021 |
| 2606:5280::/32 | 4.3B × /64 | ARIN | US | 17th Jul 2015 |
| 2606:52c0::/32 | 4.3B × /64 | ARIN | US | 21st May 2021 |
| 2606:5380::/32 | 4.3B × /64 | ARIN | US | 20th Jul 2015 |
| 2606:53c0::/32 | 4.3B × /64 | ARIN | US | 24th May 2021 |
| 2606:5400::/32 | 4.3B × /64 | ARIN | US | 9th Sept 2010 |
| 2606:540::/32 | 4.3B × /64 | ARIN | US | 29th Oct 2020 |
| 2606:5580::/32 | 4.3B × /64 | ARIN | US | 21st Jul 2015 |
| 2606:5640::/32 | 4.3B × /64 | ARIN | US | 3rd Jun 2021 |
| 2606:5740::/32 | 4.3B × /64 | ARIN | US | 3rd Jun 2021 |
| 2606:5800::/32 | 4.3B × /64 | ARIN | US | 20th May 2010 |
| 2606:580::/32 | 4.3B × /64 | ARIN | US | 5th Mar 2015 |
| 2606:5840::/32 | 4.3B × /64 | ARIN | US | 9th Jun 2021 |