optimize.dk is a .dk domain served by 2 nameservers (ns1.efclausen.dk, ns2.efclausen.dk). It was already in the .dk zone when our tracking began on 16 June 2026. Its website address 185.21.40.251 is hosted by team.blue Denmark A/S (AS48854) in Denmark. Mail is handled by optimize-dk.mail.protection.outlook.com. The zone is DNSSEC-signed and validates, publishes a 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.
| IP | TTL | PTR | ASN | ISP / Org | CIDR | Country | City |
|---|---|---|---|---|---|---|---|
| 185.21.40.251 | 3600s | linux8.curanet.dk | AS48854 | team.blue Denmark A/S | 185.21.40.0/22 | 🇩🇰 Denmark | — |
| Service | CNAME / IP |
|---|---|
| 🔷 Autodiscover | autodiscover.outlook.com → 40.98.16.67 |
| 🔶 Autoconfig | 185.21.42.35 |
| TXT Record |
|---|
| google-site-verification=VybJQ8YikNdK3mEeN6m_506bHyKOjNR_Mp9hDR62YoI |
| v=spf1 include:spf.protection.outlook.com -all |
| Policy | Record (optimize.dk) |
|---|---|
| -all (hard fail) | v=spf1 include:spf.protection.outlook.com -all |
| Policy | Record (_dmarc.optimize.dk) |
|---|---|
| p=reject | v=DMARC1; p=reject; pct=100; fo=1 |
| www CNAME | optimize.dk (all on optimize.dk) → 185.21.40.251 (AS48854) |
| www vs bare domain | Same network |
| Wildcard | Yes: any name under the zone resolves |
| Denial of existence | NSEC3 · 1 iteration · 1-byte salt RFC 9276 recommends 0 iterations and no salt |
| CDS / CDNSKEY | None 0 CDS, 0 CDNSKEY |
| Selector | CNAME | Key |
|---|---|---|
| selector1 | selector1-optimize-dk._domainkey.optimizedk.onmicrosoft.com | 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 | 2026041301 |
| Primary NS (MNAME) | ns1.efclausen.dk |
| Responsible (RNAME) | hostmaster@curanet.dk |
| Refresh | 14400s |
| Retry | 3600s |
| Expire | 1209600s |
| Minimum (neg-cache TTL) | 300s |
| Scanned At | Duration | Records | DNSSEC |
|---|---|---|---|
| 2026-10-01 18:21:26 | 946ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-09-30 18:06:29 | 1007ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-08-27 01:55:10 | 1106ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-27 02:41:29 | 857ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-25 12:06:26 shown | 1049ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-24 18:51:32 | 731ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-22 01:03:37 | 996ms | 0 NS 0 A 0 MX | ❓ Unknown |
| 2026-06-21 06:45:39 | 765ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-19 19:01:09 | 1279ms | 2 NS 1 A 1 MX | ⚠️ Bogus |
| 2026-06-17 22:46:18 | 3796ms | 2 NS 1 A 1 MX | 🔒 Secure |