Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
ussteel.com
No
None
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-20 14:16:14 UTC · ↺ Refresh
MX Hostnames
No MX records found.
MX Priorities
No priority data.
A / AAAA Records
- 170.191.2.47 (no PTR)
Mail Server IPs
No IPs resolved.
SOA Record
Raw SOA
ns3.level3.net postmaster.ns3.level3.net 2025121602 21600 900 1209600 86400
Primary NS (mname)
ns3.level3.net
Admin Email (rname)
postmaster@ns3.level3.net
Serial
2025121602
Refresh
21600s
Retry
900s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
ns3.level3.net
ns4.level3.net
SPF Record
✓ Strict (-all)
v=spf1 mx ip4:199.248.185.120/32 -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected]; ruf=mailto:[email protected]
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 13 found
google._domainkey
selector1._domainkey
selector2._domainkey
default._domainkey
mail._domainkey
dkim._domainkey
k1._domainkey
s1._domainkey
s2._domainkey
zoho._domainkey
sendgrid._domainkey
mxvault._domainkey
amazonses._domainkey
⚠ Public key (p=) missing in DKIM record for selector google.
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
3 records- google-site-verification=ODA78qRek9dfoE8qSFuyTDM_4-lgKiaDvEB-uHPc_34
- facebook-domain-verification=odbzn4j6za8wtv4z4y43qz5gvk7vuf
- SPFv=spf1 mx ip4:199.248.185.120/32 -all
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