Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
hc3.io
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-19 08:00:02 UTC · ↺ Refresh
MX Hostnames
- hc3-io.mail.protection.outlook.com
MX Priorities
- hc3-io.mail.protection.outlook.com: 0
A / AAAA Records
- 199.60.103.119 (no PTR)
- 199.60.103.19 (no PTR)
Mail Server IPs
- 52.101.41.22 ↩ mail-sj2pr05cu00406.inbound.protection.outlook.com
- 52.101.194.4 ↩ mail-ch4pr04cu00104.inbound.protection.outlook.com
- 52.101.9.24 ↩ mail-bl2pr02cu00400.inbound.protection.outlook.com
- 52.101.10.12 ↩ mail-bn1pr21cu00204.inbound.protection.outlook.com
- 2a01:111:f403:c902::1 ↩ mail-sj2pr05cu00401.inbound.protection.outlook.com
- 2a01:111:f403:c922:: ↩ mail-bl0pr03cu00200.inbound.protection.outlook.com
- 2a01:111:f403:f90a::1 ↩ mail-bn8pr03cu00201.inbound.protection.outlook.com
- 2a01:111:f403:c801::1 ↩ mail-sn1pr0501cu00101.inbound.protection.outlook.com
SOA Record
Raw SOA
ns-848.awsdns-42.net awsdns-hostmaster.amazon.com 1 7200 900 1209600 86400
Primary NS (mname)
ns-848.awsdns-42.net
Admin Email (rname)
awsdns-hostmaster@amazon.com
Serial
1
Refresh
7200s
Retry
900s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
ns-848.awsdns-42.net
ns-1249.awsdns-28.org
ns-1568.awsdns-04.co.uk
ns-26.awsdns-03.com
SPF Record
✓ Strict (-all)
v=spf1 a mx ip4:64.132.116.2 ip4:12.107.109.146 include:22543518.spf06.hubspotemail.net include:spf.protection.outlook.com include:spfa.cpmails.com include:_spf.psm.knowbe4.com -all
📊 DNS lookups: 6/10
✓ 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
✓ 3 found
google._domainkey
selector1._domainkey
selector2._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: google
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
17 records- knowbe4-site-verification=2db40d9b623f988ef33298869509264a
- aej08nha96eh302479p6hbg755
- c476c2a6-f214-4cb2-b05f-01b9a943bde7
- canva-site-verification=H-vfoEbKT1SARKx5eM8XOQ
- ZOOM_verify_jBxgyfzm9l3hlzXYqxkAMg
- d33d1385-aa46-4f82-acf1-a4dfafb3c3bb
- site24x7-signals-domain-verification=cf172f58cbca5c9cf5a6f65fc34463b9
- jetbrains-domain-verification=1ow37wo6qh9rtsvryba8q8dpl
- MS=ms47996760
- google-site-verification=VNBL0KX-RbjhfpEQ8P8aBFA1Nb9MjlQyBpTVJXtJ6Bs
- zapier-domain-verification-challenge=05b9d6d0-4e7b-47a2-b04c-5de92d4a4b6e
- atlassian-domain-verification=eNCHgNTBUaoYyUCghHExeMhTHjkj4Eb5Ygeusu1JRPwuM8jUgoSmBeiGpof0K2pbapple-domain-verification=utEHqfnNKRpbI47Z
- a4795f49-38f5-44f0-af99-3a2f8c00c472
- virtru-site-verify=VT4M4vKiCoB2Bx2TAMRs2y6T6uo38wqrXnPMpY2g
- duo_sso_verification=IQzwkSontorandwW4tUdg4N634dXlEoIdu9Unju0IeuTaMokZMLoiVf6JbLlHfMw
- SPFv=spf1 a mx ip4:64.132.116.2 ip4:12.107.109.146 include:22543518.spf06.hubspotemail.net include:spf.protection.outlook.com include:spfa.cpmails.com include:_spf.psm.knowbe4.com -all
- google-site-verification=5RRk1BamBkC7ORV_kjN61Gte-MGTa0U49f3Y6KHrWtw
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