Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
coltbuilders.com
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-19 22:08:59 UTC · ↺ Refresh
MX Hostnames
- mx-01-us-east-2.prod.hydra.sophos.com
- mx-02-us-east-2.prod.hydra.sophos.com
MX Priorities
- mx-01-us-east-2.prod.hydra.sophos.com: 10
- mx-02-us-east-2.prod.hydra.sophos.com: 20
A / AAAA Records
- 104.154.71.187 ↩ 187.71.154.104.bc.googleusercontent.com
Mail Server IPs
- 3.135.48.136 ↩ ec2-3-135-48-136.us-east-2.compute.amazonaws.com
- 18.218.105.173 ↩ ec2-18-218-105-173.us-east-2.compute.amazonaws.com
- 18.189.107.171 ↩ ec2-18-189-107-171.us-east-2.compute.amazonaws.com
SOA Record
Raw SOA
melissa.ns.cloudflare.com dns.cloudflare.com 2399046253 10000 2400 604800 1800
Primary NS (mname)
melissa.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2399046253
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
nick.ns.cloudflare.com
melissa.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf0.coltbuilders.com -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; pct=100; rua=mailto:[email protected]
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 392 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
7 records- SPFv=spf1 include:spf0.coltbuilders.com -all
- ZOOM_verify_3VSdgDIjR4qYOf3KONp59g
- adobe-idp-site-verification=fddf630f86422ad5ec9024813b4b2ba41ff6519f5d82a0ded81f214c414a79ad
- apple-domain-verification=aLIgw1QLZh7yk7d7
- smartsheet-site-validation=B4klia9ujeBsSqahhmL-z6sBKAtpjaZM
- sophos-domain-verification=39918c378fb5b2966eaf9df0c28426d83c33cb3a2001e7791ad781e301390b07
- sophos-domain-verification=4a9b571203676e93ca83fe2d66aaedefdb27d95e
Free · No signup required
Add email validation to your forms
Block disposable emails, validate MX records, detect role accounts — unlimited, forever free.
<script src="https://check.verifyswift.com/"></script>
One line of code · Works on any site
See demo & docs
Deep verification
Full email verification for coltbuilders.com
SMTP handshake, catch-all detection, custom validation rules, actual deliverability tests, and more.
No credit card required
Get 1,000 Free Credits