Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
sierracredit.com
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-17 20:08:06 UTC · ↺ Refresh
MX Hostnames
- gw.mail.tekwerks.com
MX Priorities
- gw.mail.tekwerks.com: 10
A / AAAA Records
- 38.75.43.244 ↩ tws.tekwerks.com
Mail Server IPs
- 38.75.43.183 ↩ gw.mail.tekwerks.com
SOA Record
Raw SOA
ns-357.awsdns-44.com awsdns-hostmaster.amazon.com 1 7200 900 1209600 86400
Primary NS (mname)
ns-357.awsdns-44.com
Admin Email (rname)
awsdns-hostmaster@amazon.com
Serial
1
Refresh
7200s
Retry
900s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
ns-1259.awsdns-29.org
ns-1651.awsdns-14.co.uk
ns-357.awsdns-44.com
ns-590.awsdns-09.net
SPF Record
✓ Strict (-all)
v=spf1 ip4:38.75.43.179 a:mail.sierracredit.com a:k-mail-3.tekwerks.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
✗ None detectedNo DKIM records found for common selectors — your provider may use a custom selector name.
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
1 record- SPFv=spf1 ip4:38.75.43.179 a:mail.sierracredit.com a:k-mail-3.tekwerks.com -all
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 sierracredit.com
SMTP handshake, catch-all detection, custom validation rules, actual deliverability tests, and more.
No credit card required
Get 1,000 Free Credits