IP Prefix
IPv4
104.21.16.0/20
Aggregated from public BGP, CT logs, our scan layer, honeypots and global probes.
Origin AS
AS13335
RPKI
1 ROAs
Open IPs
3,674
last 90 d
Network
Anycast
Cloudflare
Routing
Origin AS
Holder
Cloudflare
Prefix Length
/20
Multi-Origin
No
Last refresh
2026-07-21 19:59:50
RPKI Validity
max-len 20
valid
arin
RIR Allocation
Registry
ARIN
Country
Status
Allocated
Allocated
2014-03-28
Delegated block
104.16.0.0 + 1,048,576 addrs
Geographic Announcement
Anycast — Cloudflare.
This prefix is announced from many PoPs worldwide simultaneously. The MaxMind "ZZ" code below reflects "no single country" rather than "unknown" — the route taken depends on the BGP best-path of the querying ASN.
GeoIP attribution from MaxMind GeoLite2 (CC-BY-SA). The starting address of the prefix maps to:
| Country | Continent | Ranges |
|---|---|---|
| ZZ Anycast / no single country | 1 |
Sample IPs in this Prefix
| IP | Open ports | Last scan |
|---|---|---|
| 104.21.20.196 | 7 | 2026-07-20 10:48:09.000 |
| 104.21.17.77 | 7 | 2026-07-19 07:27:33.000 |
| 104.21.17.190 | 7 | 2026-07-18 08:51:51.000 |
| 104.21.30.34 | 6 | 2026-07-21 23:54:51.000 |
| 104.21.26.193 | 6 | 2026-07-21 21:17:52.000 |
| 104.21.28.167 | 6 | 2026-07-21 13:23:21.000 |
| 104.21.28.202 | 6 | 2026-07-21 12:35:42.000 |
| 104.21.22.131 | 6 | 2026-07-21 11:17:08.000 |
| 104.21.29.45 | 6 | 2026-07-21 05:45:29.000 |
| 104.21.23.109 | 6 | 2026-07-21 02:21:31.000 |
| 104.21.30.247 | 6 | 2026-07-19 22:19:17.000 |
| 104.21.29.54 | 6 | 2026-07-19 16:51:52.000 |
| 104.21.27.116 | 6 | 2026-07-19 00:24:23.000 |
| 104.21.26.221 | 6 | 2026-07-18 18:19:27.000 |
| 104.21.26.96 | 6 | 2026-07-17 16:09:00.000 |
| 104.21.31.253 | 6 | 2026-07-17 14:13:19.000 |
| 104.21.23.187 | 6 | 2026-07-17 05:08:49.000 |
| 104.21.26.32 | 6 | 2026-06-23 11:38:58.000 |
| 104.21.30.69 | 6 | 2026-06-22 23:37:03.000 |
| 104.21.19.35 | 6 | 2026-06-22 19:04:26.000 |
| 104.21.18.219 | 6 | 2026-06-20 15:39:55.000 |
| 104.21.16.78 | 6 | 2026-06-19 19:56:15.000 |
| 104.21.30.116 | 5 | 2026-07-22 00:31:02.000 |
| 104.21.20.150 | 5 | 2026-07-22 00:30:54.000 |
| 104.21.17.124 | 5 | 2026-07-22 00:30:10.000 |
Hosted Domains
Domains that resolve to any address in this prefix — aggregated across the whole subnet. 1,173,149 distinct domains seen; top by span shown.
History
Prefix-event history pending
Origin AS changes, ROA add/drop events, multi-origin episodes and withdrawals require snapshot-diffing across BGP crawls. The data accumulates as the archive grows — full ReplacingMergeTree compaction makes point-in-time event extraction unavailable for now.