duff.dk is a .dk domain served by 2 nameservers (mona.ns.cloudflare.com, stan.ns.cloudflare.com). It was registered on 11 May 1998 (WHOIS) and was already in the .dk zone when our tracking began on 16 June 2026. Its website address 104.21.28.195 is hosted by Cloudflare, Inc. (AS13335). Mail is handled by aspmx.l.google.com, alt1.aspmx.l.google.com and 5 more. The zone is DNSSEC-signed and validates, publishes a DMARC policy and is reachable over IPv6. Below are all of its DNS records from our latest scan: nameservers, A/AAAA, MX, TXT, SPF, DMARC, CAA, TLSA/DANE, MTA-STS, SRV and more.
| IP | TTL | PTR | ASN | ISP / Org | CIDR | Country | City |
|---|---|---|---|---|---|---|---|
| 104.21.28.195 | 300s | — | AS13335 | Cloudflare, Inc. | 104.21.0.0/17 | — | — |
| 172.67.147.106 | 300s | — | AS13335 | Cloudflare, Inc. | 172.67.128.0/17 | — | — |
| IPv6 Address | TTL | PTR | ASN | ISP / Org | CIDR | Country | City |
|---|---|---|---|---|---|---|---|
| 2606:4700:3034::ac43:936a | 300s | — | AS13335 | Cloudflare, Inc. | 2606:4700:3000:0:0:0:0:0/42 | — | — |
| 2606:4700:3035::6815:1cc3 | 300s | — | AS13335 | Cloudflare, Inc. | 2606:4700:3000:0:0:0:0:0/42 | — | — |
| Priority | Target | SvcParams |
|---|---|---|
| 1 service | . | alpn="h3,h2" ipv4hint=104.21.28.195,172.67.147.106 ech=AEX+DQBBWgAgACA7xsERYDjDfCLkDiL2J2aFI/DxvJ1s8W8zy0hj0VipdwAEAAEAAQASY2xvdWRmbGFyZS1lY2guY29tAAA= ipv6hint=2606:4700:3034::ac43:936a,2606:4700:3035::6815:1cc3 |
| TXT Record |
|---|
| 16de091ba0a169f3aab4545ad050398a |
| v=spf1 include:_spf.google.com ~all |
| Policy | Record (duff.dk) |
|---|---|
| ~all (soft fail) | v=spf1 include:_spf.google.com ~all |
| Policy | Record (_dmarc.duff.dk) |
|---|---|
| p=reject | v=DMARC1; p=reject; pct=100 |
| www | 104.21.28.195 172.67.147.106 2606:4700:3034::ac43:936a 2606:4700:3035::6815:1cc3 (AS13335) (address records, no CNAME) |
| www vs bare domain | Same network |
| Wildcard | No |
| Denial of existence | Compact NSEC (RFC 9824, "black lies") not walkable |
| CDS / CDNSKEY | Published: key rollovers can be automated with the registry (RFC 7344/8078) 1 CDS, 1 CDNSKEY |
| Selector | CNAME | Key |
|---|---|---|
| — | RSA · ~1024 bit below 2048 bit |
DKIM selectors can't be listed, so we check the common ones (Microsoft 365, Google, Mailchimp, SendGrid, generic). Keys under other selectors aren't shown.
DNS lookups: 1/10 · policy: ~all
No problems found| Check | Result |
|---|---|
| Validation Status | 🔒 Secure |
| AD Flag (resolver validates) | ✓ Set |
| DS Record | ✓ Found |
| DNSKEY Record | ✓ Found |
| Flags | fully validated |
| Field | Value |
|---|---|
| Serial | 2417482830 |
| Primary NS (MNAME) | mona.ns.cloudflare.com |
| Responsible (RNAME) | dns@cloudflare.com |
| Refresh | 10000s |
| Retry | 2400s |
| Expire | 604800s |
| Minimum (neg-cache TTL) | 1800s |
| Field | Value |
|---|---|
| Registrar | Punktum dk A/S (direct) |
| Registered | 1998-05-11 |
| Expires | 2027-06-30 (251d) |
Other .dk domains whose WHOIS registrant has the same name and postal address. Matched on a keyed hash: the registrant's details are not stored or shown. Covers only domains whose WHOIS we have fetched (refreshed about monthly).
| Domain | Registrar |
|---|---|
| kool.dk | Punktum dk A/S (direct) |
| Scanned At | Duration | Records | DNSSEC |
|---|---|---|---|
| 2026-10-15 23:49:55 shown | 2078ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-10-14 18:25:11 | 1640ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-09-26 20:15:04 | 804ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-09-22 22:55:55 | 942ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-08-27 19:00:31 | 1205ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-08-17 00:28:54 | 6775ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-08-06 00:58:41 | 3185ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-07-22 14:52:41 | 10013ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-07-12 17:20:37 | 1865ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-06-25 12:51:01 | 4498ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-06-21 15:25:05 | 3213ms | 2 NS 2 A 7 MX | 🔒 Secure |
| 2026-06-17 04:55:09 | 655ms | 2 NS 2 A 7 MX | 🔒 Secure |