blue52.dk is a .dk domain served by 3 nameservers (ns1.e-studio.dk, ns2.e-studio.dk, ns3.e-studio.dk). It was registered on 15 February 2022 (WHOIS) and was already in the .dk zone when our tracking began on 16 June 2026. Its website address 193.200.90.180 is hosted by Christian Ebsen ApS (AS62121) in Denmark. Mail is handled by mx4.spamfri.dk, mx2.spamfri.dk and 2 more. The zone is not DNSSEC-signed, has no DMARC policy and has no IPv6 address. Below are all of its DNS records from this scan: nameservers, A/AAAA, MX, TXT, SPF, DMARC, CAA, TLSA/DANE, MTA-STS, SRV and more.
| Nameserver | IP addresses | PTR | ASN / ISP |
|---|---|---|---|
| ns1.e-studio.dk | — | — | — |
| ns2.e-studio.dk | — | — | — |
| ns3.e-studio.dk | — | — | — |
| IP | TTL | PTR | ASN | ISP / Org | CIDR | Country | City |
|---|---|---|---|---|---|---|---|
| 193.200.90.180 | — | web8.e-studio.dk | AS62121 | Christian Ebsen ApS | 193.200.90.0/23 | 🇩🇰 Denmark | — |
| Priority | TTL | Mail Server | IP addresses | PTR | ASN |
|---|---|---|---|---|---|
| 10 | — | mx4.spamfri.dk | 193.200.91.108 | mx4.spamfri.dk | AS62121 Christian Ebsen ApS |
| 20 | — | mx2.spamfri.dk | 193.200.91.109 | mx2.spamfri.dk | AS62121 Christian Ebsen ApS |
| 30 | — | mx3.spamfri.dk | 62.69.152.43 62.69.152.43 |
43.34-46.152.69.62.in-addr.arpa mx3.spamfri.dk |
AS47527 DLX A/S AS47527 DLX A/S |
| 40 | — | mx1.spamfri.dk | 195.242.131.16 | mx1.spamfri.dk | AS62121 Christian Ebsen ApS |
| TXT Record |
|---|
| v=spf1 include:_spf.e-studio.dk -all |
| Policy | Record (blue52.dk) |
|---|---|
| -all (hard fail) | v=spf1 include:_spf.e-studio.dk -all |
| www CNAME | blue52.dk (all on blue52.dk) |
| www vs bare domain | Same network |
| Wildcard | No |
| Denial of existence | NSEC3 · 7 iterations · 8-byte salt RFC 9276 recommends 0 iterations and no salt |
| CDS / CDNSKEY | None 0 CDS, 0 CDNSKEY |
| Selector | CNAME | Key |
|---|---|---|
| default | — | RSA · ~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| Service / Owner | Type | Cert association |
|---|---|---|
| SMTP _25._tcp.mx1.spamfri.dk | DANE-EE · SPKI · SHA-256 | 884451547A03D0AC2F628D943839BAA6… |
| SMTP _25._tcp.mx2.spamfri.dk | DANE-EE · SPKI · SHA-256 | 6598C93F79B95376BB8099E9AC862167… |
| SMTP _25._tcp.mx3.spamfri.dk | DANE-EE · SPKI · SHA-256 | BBFB0694919290E5BC9D6E2C6F47D846… |
| SMTP _25._tcp.mx4.spamfri.dk | DANE-EE · SPKI · SHA-256 | 4EE743A99328AEF5142706CA5FD3AD61… |
| Check | Result |
|---|---|
| Validation Status | 🔓 Insecure |
| AD Flag (resolver validates) | ✗ Not set |
| DS Record | ✗ Not found |
| DNSKEY Record | ✓ Found |
| Flags | unsigned answer |
| Field | Value |
|---|---|
| Serial | 2026052101 |
| Primary NS (MNAME) | ns1.e-studio.dk |
| Responsible (RNAME) | hostmaster@mailrelay.e-studio.dk |
| Refresh | 3600s |
| Retry | 1800s |
| Expire | 1209600s |
| Minimum (neg-cache TTL) | 86400s |
| Field | Value |
|---|---|
| Registrar | Punktum dk A/S (direct) |
| Registered | 2022-02-15 |
| Expires | 2028-02-14 (485d) |
| Scanned At | Duration | Records | DNSSEC |
|---|---|---|---|
| 2026-09-30 13:52:03 | 683ms | 3 NS 1 A 4 MX | 🔓 Insecure |
| 2026-09-29 20:47:48 | 581ms | 3 NS 1 A 4 MX | 🔓 Insecure |
| 2026-09-26 06:19:45 | 656ms | 3 NS 1 A 4 MX | 🔓 Insecure |
| 2026-09-21 09:34:13 | 1391ms | 3 NS 1 A 4 MX | 🔓 Insecure |
| 2026-07-21 19:15:01 | 1235ms | 3 NS 1 A 4 MX | 🔓 Insecure |
| 2026-07-01 23:26:21 | 868ms | 3 NS 1 A 4 MX | 🔓 Insecure |
| 2026-06-16 15:09:23 | 496ms | 3 NS 1 A 4 MX | 🔓 Insecure |
| 2026-06-16 15:08:49 | 2934ms | 3 NS 1 A 4 MX | 🔓 Insecure |
| 2026-06-16 15:06:58 | 2366ms | 3 NS 1 A 4 MX | 🔓 Insecure |
| 2026-06-16 15:01:06 shown | 703ms | 3 NS 1 A 4 MX | 🔓 Insecure |