duncker-humblot.de

Valid Email Server

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
duncker-humblot.de
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No

Checked via [email protected] · 2026-03-26 09:27:36 UTC · ↺ Refresh

MX Hostnames

  • mavas3.cbxnet.de
  • mavas2.cbxnet.de
  • dunckerhumblot-de01i.mail.protection.outlook.com
  • mail.duncker-humblot.de

MX Priorities

  • dunckerhumblot-de01i.mail.protection.outlook.com: 200
  • mail.duncker-humblot.de: 250
  • mavas2.cbxnet.de: 180
  • mavas3.cbxnet.de: 190

A / AAAA Records

  • 104.26.0.13
  • 172.67.72.30
  • 104.26.1.13
  • 2606:4700:20::681a:d
  • 2606:4700:20::681a:10d
  • 2606:4700:20::ac43:481e

Mail Server IPs

  • 52.101.170.0 ↩ mail-fr5p281cu00500.inbound.protection.outlook.com
  • 52.101.168.0 ↩ mail-beup281cu00100.inbound.protection.outlook.com
  • 52.101.170.1 ↩ mail-fr4p281cu03101.inbound.protection.outlook.com
  • 52.101.170.2 ↩ mail-fr6p281cu00202.inbound.protection.outlook.com
  • 2a01:111:f403:ca27:: ↩ mail-beup281cu00100.inbound.protection.outlook.com
  • 2a01:111:f403:ca2d::1 ↩ mail-fr4p281cu03101.inbound.protection.outlook.com
  • 2a01:111:f403:ca2d::2 ↩ mail-fr6p281cu00202.inbound.protection.outlook.com
  • 2a01:111:f403:ca2d:: ↩ mail-fr5p281cu00500.inbound.protection.outlook.com
  • 212.87.46.93 ↩ autodiscover.duncker-humblot.de
  • 212.87.33.79 ↩ mavas2.cbxnet.de
  • 212.87.33.80

SOA Record

Raw SOA joyce.ns.cloudflare.com dns.cloudflare.com 2399410887 10000 2400 604800 1800
Primary NS (mname)
joyce.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2399410887
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s

Nameservers (NS)

lars.ns.cloudflare.com
joyce.ns.cloudflare.com

SPF Record

✓ Soft Fail (~all)
v=spf1 ip4:212.87.32.0/19 ip4:5.9.36.108 include:sendgrid.net include:spf.crsend.com include:_spf.wirth-horn.de include:spf.protection.outlook.com ~all
📊 DNS lookups: 4/10
~ Soft fail (~all) — moderate enforcement

DMARC Record

✗ p=none
v=DMARC1;p=none;pct=100;
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed · DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)

DKIM Selectors

✓ 2 found
s1._domainkey
s2._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: s1

Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses

All TXT Records

2 records
  • SPFv=spf1 ip4:212.87.32.0/19 ip4:5.9.36.108 include:sendgrid.net include:spf.crsend.com include:_spf.wirth-horn.de include:spf.protection.outlook.com ~all
  • MS=ms15482939
Free · No signup required
Add email validation to your forms

Block disposable emails, validate MX records, detect role accounts — unlimited, forever free.

<script src="https://check.verifyswift.com/"></script>
One line of code · Works on any site
See demo & docs
Deep verification
Full email verification for duncker-humblot.de

SMTP handshake, catch-all detection, custom validation rules, actual deliverability tests, and more.

No credit card required
Get 1,000 Free Credits