Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
sizmek.com
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-20 14:20:15 UTC · ↺ Refresh
MX Hostnames
- amazon-smtp.amazon.com
MX Priorities
- amazon-smtp.amazon.com: 10
A / AAAA Records
No A/AAAA records found.
Mail Server IPs
- 44.231.24.41 ↩ smtp03.us-west-2.mail-perimeter.amazon.com
SOA Record
Raw SOA
ns-2028.awsdns-61.co.uk awsdns-hostmaster.amazon.com 1 7200 900 1209600 86400
Primary NS (mname)
ns-2028.awsdns-61.co.uk
Admin Email (rname)
awsdns-hostmaster@amazon.com
Serial
1
Refresh
7200s
Retry
900s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
ns-343.awsdns-42.com
ns-556.awsdns-05.net
ns-1174.awsdns-18.org
ns-2028.awsdns-61.co.uk
SPF Record
✓ Strict (-all)
v=spf1 include:amazon.com -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; pct=100; rua=mailto:[email protected];ruf=mailto:[email protected]
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✗ None detectedNo 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
1 record- SPFv=spf1 include:amazon.com -all
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