Domain Overview
DNS: ✓ 17d ago
Checker: ✓ 17d ago
sdf.org
Disposable
✓ Yes
Unknown
⚠ Yes
Yes
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-05-24 13:10:19 UTC · ↺ Refresh
MX Hostnames
- mx.sdf.org
MX Priorities
- mx.sdf.org: 50
A / AAAA Records
- 205.166.94.16 ↩ sdf.org
Mail Server IPs
- 205.166.94.24 ↩ mx.sdf.org
SOA Record
Raw SOA
sdf.org hostmaster.sdf.org 2026052411 14400 1800 604800 3600
Primary NS (mname)
sdf.org
Admin Email (rname)
hostmaster@sdf.org
Serial
2026052411
Refresh
14400s
Retry
1800s
Expire
604800s
Minimum TTL
3600s
Nameservers (NS)
ns-a.sdf.org
ns-d.sdf.org
ns-c.sdf.org
ns-b.sdf.org
SPF Record
✓ Strict (-all)
v=spf1 ip4:205.166.94.0/24 -all
📊 DNS lookups: 0/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1;p=quarantine;sp=quarantine;rua=mailto:[email protected]
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
↳ Subdomain policy: quarantine
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
2 records- google-site-verification=f_IZGvm9STb9qD_OALNWOBBqguBJc0eJXWTvTkKjXSc
- SPFv=spf1 ip4:205.166.94.0/24 -all
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