Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
on24.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-18 02:46:43 UTC · ↺ Refresh
MX Hostnames
- on24-com.mail.protection.outlook.com
MX Priorities
- on24-com.mail.protection.outlook.com: 10
A / AAAA Records
- 162.159.135.42 (no PTR)
Mail Server IPs
- 52.101.10.12 ↩ mail-bn1pr21cu00204.inbound.protection.outlook.com
- 52.101.50.7 ↩ mail-co1pr21cu00207.inbound.protection.outlook.com
- 52.101.10.5 ↩ mail-bn6pr04cu00105.inbound.protection.outlook.com
- 52.101.9.17 (no PTR)
- 2a01:111:f403:f90a:: ↩ mail-bn6pr02cu00300.inbound.protection.outlook.com
- 2a01:111:f403:f802::3 ↩ mail-sj0pr03cu01403.inbound.protection.outlook.com
- 2a01:111:f403:f907::1 ↩ mail-dm1pr04cu00201.inbound.protection.outlook.com
- 2a01:111:f403:c91d:: ↩ mail-mw2pr04cu00100.inbound.protection.outlook.com
SOA Record
Raw SOA
dns4.on24.com sysmgr.on24.com 2850253889 7200 31104000 1209600 1800
Primary NS (mname)
dns4.on24.com
Admin Email (rname)
sysmgr@on24.com
Serial
2850253889
Refresh
7200s
Retry
31104000s
Expire
1209600s
Minimum TTL
1800s
Nameservers (NS)
a13-64.akam.net
a1-97.akam.net
a26-66.akam.net
a12-67.akam.net
a7-64.akam.net
a8-67.akam.net
SPF Record
✓ Strict (-all)
v=spf1 ip4:199.83.44.0/22 include:spf.protection.outlook.com include:mktomail.com include:mail.zendesk.com -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; fo=1; rua=mailto:[email protected]; ruf=mailto:[email protected];
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 4 found
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._domainkey
✓ Public key: 216 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
2 records- stripe-verification=84830C36EB1B7AAEABCCDFC9DDAB69C48A2BFB7117D7326450F2C886329ACA55
- SPFv=spf1 ip4:199.83.44.0/22 include:spf.protection.outlook.com include:mktomail.com include:mail.zendesk.com -all
Full email verification for on24.com
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