21d.co.uk

Valid Email Server
Domain Lookup › 21d.co.uk

Domain Overview

DNS: ✓ 1mo ago Checker: ✓ 1mo ago
21d.co.uk
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]

Checked via [email protected] · 2026-08-26 13:12:06 UTC · ↺ Refresh

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MX Hostnames

  • 21d-co-uk.mail.protection.outlook.com

MX Priorities

  • 21d-co-uk.mail.protection.outlook.com: 10

A / AAAA Records

  • 172.67.140.225 (no PTR)
  • 104.21.81.77 (no PTR)
  • 2606:4700:3037::ac43:8ce1
  • 2606:4700:3035::6815:514d

Mail Server IPs

  • 52.101.89.0 ↩ mail-lo2p265cu02300.inbound.protection.outlook.com
  • 52.101.89.1 ↩ mail-lo0p265cu00201.inbound.protection.outlook.com
  • 52.101.99.0 ↩ mail-cwxp265cu00600.inbound.protection.outlook.com
  • 52.101.89.2 ↩ mail-lo3p265cu00302.inbound.protection.outlook.com
  • 2a01:111:f403:ca0b:: ↩ mail-lo2p265cu02300.inbound.protection.outlook.com
  • 2a01:111:f403:ca0b::1 ↩ mail-lo3p265cu00301.inbound.protection.outlook.com
  • 2a01:111:f403:ca0b::2 ↩ mail-lo0p265cu00202.inbound.protection.outlook.com
  • 2a01:111:f403:ca1a::1 ↩ mail-cwxp265cu00601.inbound.protection.outlook.com

SOA Record

Raw SOA maria.ns.cloudflare.com dns.cloudflare.com 2411410487 10000 2400 604800 1800
Primary NS (mname)
maria.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2411410487
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s

Nameservers (NS)

maria.ns.cloudflare.com
noah.ns.cloudflare.com

SPF Record

✓ Strict (-all)
v=spf1 +mx +ip4:35.214.61.229 include:edgepilot.com include:145013830.spf06.hubspotemail.net -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict 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

✓ 1 found
default._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: default

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

All TXT Records

8 records
  • google-site-verification=Fg-IJ5Nf0Wc9fy0bBQSeaX373pIeJuUQZsrrORKfLyQ
  • google-site-verification=nFX3V0793FFL0M7H_UlarDt6CV8N4iSR47DIjjzLr8k
  • nSqMIWxA2G1CK3wWJ69TfIXU1SeeCmdN
  • SPFv=spf1 +mx +ip4:35.214.61.229 include:edgepilot.com include:145013830.spf06.hubspotemail.net -all
  • MS=ms82781339
  • ahrefs-site-verification_1891f8bc9b56cd61971e928ca7a61a55b09a924d591e1e33a5f7fd11d22ea1e2
  • anthropic-domain-verification-85w5ve=kJLiHSeY4wJTT0vtSkPpddObK
  • facebook-domain-verification=dkau960ebqato6r7nmm6n97qrk7non
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