Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
fsr.uk.com
Yes
✓ Yes
Barracuda
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-26 23:45:24 UTC · ↺ Refresh
MX Hostnames
- d221487.b.ess.uk.barracudanetworks.com
- d221487.a.ess.uk.barracudanetworks.com
MX Priorities
- d221487.a.ess.uk.barracudanetworks.com: 5
- d221487.b.ess.uk.barracudanetworks.com: 10
A / AAAA Records
- 185.151.30.222 ↩ 185-151-30-222.ptr4.stackcp.net
Mail Server IPs
- 18.133.136.187 ↩ mail.ess.uk.barracuda.com
- 18.133.136.188 ↩ mail.ess.uk.barracuda.com
- 18.133.136.186 ↩ mail.ess.uk.barracuda.com
SOA Record
Raw SOA
ns1.stackdns.com hostmaster.stackdns.com 1737387071 1800 900 1209600 300
Primary NS (mname)
ns1.stackdns.com
Admin Email (rname)
hostmaster@stackdns.com
Serial
1737387071
Refresh
1800s
Retry
900s
Expire
1209600s
Minimum TTL
300s
Nameservers (NS)
ns3.stackdns.com
ns2.stackdns.com
ns4.stackdns.com
ns1.stackdns.com
SPF Record
✓ Strict (-all)
v=spf1 ip4:45.8.227.179 include:spf.stackmail.com include:spf.protection.outlook.com include:spf.ess.uk.barracudanetworks.com -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; pct=100; rua=mailto:[email protected]; sp=reject; aspf=r;
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
↳ Subdomain policy: reject
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
3 records- 751469
- google-site-verification=3mNSH17pP4y9TCm032-2DEsENzdMf5_qxpErIHf6qBI
- SPFv=spf1 ip4:45.8.227.179 include:spf.stackmail.com include:spf.protection.outlook.com include:spf.ess.uk.barracudanetworks.com -all
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 fsr.uk.com
SMTP handshake, catch-all detection, custom validation rules, actual deliverability tests, and more.
No credit card required
Get 1,000 Free Credits