🛠️ Free Email Diagnostic Tools
DNS Lookup & SMTP Test Tools.
Check your domain DNS records, verify SPF, DKIM and DMARC settings, and test your SMTP configuration — all in one place. 100% free, no login required.
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DNS Lookup
9 record types
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SMTP Test
Live send test
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Instant Results
No login needed
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100% Free
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DNS Lookup Tool
SPF · DKIM · DMARC · MX · A · NS · CNAME · WHOIS
Domain
Record Type
DKIM Selector
Looking up DNS records...
SMTP Test Tool
Verify your SMTP server is working correctly
SMTP Host
SMTP Port
Encryption
From Email
SMTP Username
SMTP Password
Send Test To
Connecting to SMTP server...
DNS Records Explained
What Each Record Does.
Quick reference guide for every DNS record type you can check with the tool above.
SPF
Lists servers authorised to send email from your domain — prevents spoofing and improves deliverability.
DKIM
Adds a digital signature to your outgoing emails — verifies they have not been tampered with in transit.
DMARC
Tells receiving servers what to do with emails that fail SPF or DKIM checks — quarantine or reject.
MX
Points to mail servers responsible for receiving email for your domain — essential for email routing.
A Record
Maps your domain name to an IPv4 address — connects your domain to your web server.
rDNS / PTR
Reverse DNS — verifies that an IP address belongs to a specific hostname. Critical for email reputation.
Need Expert Help?
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