Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
efficientcoolheat.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-31 01:55:02 UTC · ↺ Refresh
MX Hostnames
- efficientcoolheat-com.mail.protection.outlook.com
MX Priorities
- efficientcoolheat-com.mail.protection.outlook.com: 0
A / AAAA Records
- 185.151.30.178 ↩ 185-151-30-178.ptr4.stackcp.net
- 2a07:7800::178 (no PTR)
Mail Server IPs
- 52.101.68.16 ↩ mail-db4pr02cu00400.inbound.protection.outlook.com
- 52.101.68.29 ↩ mail-dbapr03cu00105.inbound.protection.outlook.com
- 52.101.68.39 ↩ mail-db7pr03cu00607.inbound.protection.outlook.com
- 52.101.73.24 ↩ mail-as8pr05cu00300.inbound.protection.outlook.com
- 2a01:111:f403:ca04::4 ↩ mail-db4pr02cu00204.inbound.protection.outlook.com
- 2a01:111:f403:ca09::5 ↩ mail-am1pr04cu00105.inbound.protection.outlook.com
- 2a01:111:f403:ca04::2 ↩ mail-du2pr03cu00102.inbound.protection.outlook.com
- 2a01:111:f403:ca09::d ↩ mail-as9pr05cu01305.inbound.protection.outlook.com
SOA Record
Raw SOA
ns1.stackdns.com hostmaster.stackdns.com 1770205484 1800 900 1209600 300
Primary NS (mname)
ns1.stackdns.com
Admin Email (rname)
hostmaster@stackdns.com
Serial
1770205484
Refresh
1800s
Retry
900s
Expire
1209600s
Minimum TTL
300s
Nameservers (NS)
ns4.stackdns.com
ns2.stackdns.com
ns3.stackdns.com
ns1.stackdns.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:spf.stackmail.com -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ MissingNo DMARC record — emails cannot be rejected on auth failure.
DKIM Selectors
✓ 1 found
k1._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: k1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
2 records- _globalsign-domain-verification=2-szRZx1PLf2zV7Z2MYqLOLLDzfexgt4Pn-lB_QM8U
- SPFv=spf1 include:spf.protection.outlook.com include:spf.stackmail.com -all
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