xiii.nu

Valid Email Server
Domain Lookup › xiii.nu

Domain Overview

DNS: ✓ just now Checker: ✓ just now
xiii.nu
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]

Checked via [email protected] · 2026-06-01 23:24:09 UTC · ↺ Refresh

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MX Hostnames

  • mailsec.protonmail.ch
  • mail.protonmail.ch

MX Priorities

  • mailsec.protonmail.ch: 20
  • mail.protonmail.ch: 10

A / AAAA Records

  • 23.44.203.80 ↩ a23-44-203-80.deploy.static.akamaitechnologies.com
  • 23.44.203.88 ↩ a23-44-203-88.deploy.static.akamaitechnologies.com

Mail Server IPs

  • 185.205.70.129 ↩ mailsec.protonmail.ch
  • 185.70.42.129 ↩ mailsec.protonmail.ch
  • 176.119.200.129 ↩ mailsec.protonmail.ch
  • 176.119.200.128 ↩ mail.protonmail.ch
  • 185.205.70.128 ↩ mail.protonmail.ch
  • 185.70.42.128 ↩ mail.protonmail.ch

SOA Record

Raw SOA a9-66.akam.net hostmaster.akamai.com 2019061351 43200 7200 604800 7200
Primary NS (mname)
a9-66.akam.net
Admin Email (rname)
hostmaster@akamai.com
Serial
2019061351
Refresh
43200s
Retry
7200s
Expire
604800s
Minimum TTL
7200s

Nameservers (NS)

a9-66.akam.net
a1-245.akam.net
a28-64.akam.net
a18-66.akam.net
a7-65.akam.net
a26-67.akam.net

SPF Record

✓ Soft Fail (~all)
v=spf1 include:_spf.protonmail.ch mx ~all
📊 DNS lookups: 2/10
~ Soft fail (~all) — moderate enforcement

DMARC Record

✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected]
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed · DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]

DKIM Selectors

✗ None detected

No DKIM records found for common selectors — your provider may use a custom selector name.

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

All TXT Records

2 records
  • SPFv=spf1 include:_spf.protonmail.ch mx ~all
  • protonmail-verification=bbb5e40afe694241d831de22672031997d87e82d
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