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It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today.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
85,279 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 2604:f20::/32 | 4.3B × /64 | ARIN |  US | 6th May 2025 |
| 2604:f280::/32 | 4.3B × /64 | ARIN | US | 21st Aug 2013 |
| 2604:f2c0::/32 | 4.3B × /64 | ARIN | US | 22nd Aug 2018 |
| 2604:f300::/32 | 4.3B × /64 | ARIN | US | 26th May 2011 |
| 2604:f40::/32 | 4.3B × /64 | ARIN | US | 20th Jan 2017 |
| 2604:f480::/32 | 4.3B × /64 | ARIN | US | 21st Aug 2013 |
| 2604:f500::/32 | 4.3B × /64 | ARIN | US | 27th May 2011 |
| 2604:f5c0::/32 | 4.3B × /64 | ARIN | US | 7th Sept 2018 |
| 2604:f640::/36 | 268M × /64 | ARIN | US | 7th Sept 2018 |
| 2604:f7c0::/32 | 4.3B × /64 | ARIN | US | 18th Sept 2018 |
| 2604:f800::/32 | 4.3B × /64 | ARIN |  CA | 26th Apr 2010 |
| 2604:f8c0::/32 | 4.3B × /64 | ARIN | US | 20th Sept 2018 |
| 2604:f900::/32 | 4.3B × /64 | ARIN | US | 27th May 2011 |
| 2604:f940::/32 | 4.3B × /64 | ARIN | US | 21st Sept 2018 |
| 2604:f980::/32 | 4.3B × /64 | ARIN | US | 28th Aug 2013 |
| 2604:fa80::/32 | 4.3B × /64 | ARIN | CA | 28th Aug 2013 |
| 2604:fb00::/32 | 4.3B × /64 | ARIN | US | 27th May 2011 |
| 2604:fb40::/32 | 4.3B × /64 | ARIN | US | 26th Sept 2018 |
| 2604:fc0::/32 | 4.3B × /64 | ARIN | CA | 23rd Jan 2017 |
| 2604:fc40::/32 | 4.3B × /64 | ARIN | US | 9th Feb 2026 |
| 2604:fd40::/32 | 4.3B × /64 | ARIN | US | 2nd Oct 2018 |
| 2604:fdc0::/32 | 4.3B × /64 | ARIN | US | 2nd Oct 2018 |
| 2604:ff00::/32 | 4.3B × /64 | ARIN | US | 31st May 2011 |
| 2604:ff80::/32 | 4.3B × /64 | ARIN | CA | 13th Sept 2013 |
| 2605:1040::/32 | 4.3B × /64 | ARIN | US | 5th Dec 2018 |
| 2605:10c0::/32 | 4.3B × /64 | ARIN | US | 6th Dec 2018 |
| 2605:1140::/32 | 4.3B × /64 | ARIN | US | 11th Dec 2018 |
| 2605:1180::/32 | 4.3B × /64 | ARIN | US | 22nd Oct 2013 |
| 2605:11c0::/32 | 4.3B × /64 | ARIN | CA | 11th Dec 2018 |
| 2605:1240::/32 | 4.3B × /64 | ARIN | CA | 21st Dec 2018 |
| 2605:1300::/32 | 4.3B × /64 | ARIN | CA | 3rd Jun 2011 |
| 2605:1340::/32 | 4.3B × /64 | ARIN | US | 3rd Jan 2019 |
| 2605:1380::/32 | 4.3B × /64 | ARIN | CA | 24th Oct 2013 |
| 2605:13c0::/32 | 4.3B × /64 | ARIN | US | 3rd Jan 2019 |
| 2605:1400::/32 | 4.3B × /64 | ARIN | US | 22nd Jul 2010 |
| 2605:1440::/32 | 4.3B × /64 | ARIN | US | 3rd Jan 2019 |
| 2605:1480::/32 | 4.3B × /64 | ARIN | US | 25th Oct 2013 |
| 2605:14c0::/32 | 4.3B × /64 | ARIN | US | 4th Jan 2019 |
| 2605:1580::/32 | 4.3B × /64 | ARIN | US | 25th Oct 2013 |
| 2605:160::/32 | 4.3B × /64 | ARIN | US | 20th Jul 2026 |
| 2605:1780::/32 | 4.3B × /64 | ARIN | US | 29th Oct 2013 |
| 2605:17c0::/32 | 4.3B × /64 | ARIN | US | 8th Jan 2019 |
| 2605:1840::/32 | 4.3B × /64 | ARIN | US | 15th Jan 2019 |
| 2605:19c0::/32 | 4.3B × /64 | ARIN | US | 22nd Jan 2019 |
| 2605:1a00::/32 | 4.3B × /64 | ARIN | US | 13th Dec 2010 |
| 2605:1a40::/32 | 4.3B × /64 | ARIN | US | 23rd Jan 2019 |
| 2605:1a80::/32 | 4.3B × /64 | ARIN | US | 6th Nov 2013 |
| 2605:1ac0::/32 | 4.3B × /64 | ARIN | US | 23rd Jan 2019 |
| 2605:1b80::/32 | 4.3B × /64 | ARIN | US | 6th Nov 2013 |
| 2605:1c0::/32 | 4.3B × /64 | ARIN | US | 16th Jul 2026 |