Mail Server Test
Check a mail domain for MX records, public mail host addresses, PTR records, SPF, DMARC, SMTP banner, EHLO, and STARTTLS support.
Mail Server Test checks whether a domain publishes usable mail server records and whether selected MX hosts respond like SMTP servers. Enter an email address or domain, choose how many MX hosts to test, and review DNS, authentication, and SMTP connectivity signals in one report.
This tool is designed for mail-domain health troubleshooting. It does not log in to a mailbox, send a test message, verify a recipient, or perform open-relay abuse testing.
Mail Server Test
Enter the required values and run the tool to view results.
Recommended Next Checks
Continue the same task with related tools. When possible, your current input is carried to the next page.
SMTP Test
Test SMTP server settings, TLS or STARTTLS, authentication, and optional test-message deli...
Reverse DNS Lookup
Inspect PTR records and forward-confirmed reverse DNS for an IP address.
SPF Validator
Validate Sender Policy Framework (SPF) authentication of a DNS.
DKIM Validator
Validate a DKIM selector and public key record.
How to use Mail Server Test
Enter a domain such as example.com or an email address such as [email protected]. The tool extracts the domain, finds MX records, checks the address records for the MX hosts, reviews reverse DNS, looks for common email-authentication records, and connects to the selected MX hosts on the chosen SMTP port.
What the test checks
The report includes MX priority records, public A/AAAA records for mail hosts, duplicate MX IP detection, CNAME detection, PTR coverage, SPF, DMARC, MTA-STS, TLS-RPT, SMTP banner, EHLO response, and whether STARTTLS is advertised. These checks help identify mail-routing and deliverability issues before they become outages.
What this test does not check
This tool does not authenticate with SMTP credentials, send email, retrieve mail, test a recipient mailbox, or prove final inbox placement. Recipient verification and relay testing can be unreliable or risky because many providers intentionally block or limit those SMTP commands to prevent abuse.
How to interpret results
Missing MX records usually means the domain is not configured to receive mail. Missing PTR records can harm mail reputation for servers that send mail. Missing SPF or DMARC records increases spoofing risk. A failed SMTP connection can indicate firewall rules, provider filtering, a temporary outage, or that the tested port is not intended for public server-to-server mail.
Mail server troubleshooting tips
For inbound mail delivery, start with MX records and public address records. For sender reputation, review PTR, SPF, DKIM, DMARC, and sending IP behavior. For transport security, consider MTA-STS and TLS-RPT. Use the SMTP Test tool when you need to validate authenticated submission settings separately.
Related Tools
SMTP Test
Test SMTP server settings, TLS or STARTTLS, authentication, and optional test-message delivery.
Reverse DNS Lookup
Inspect PTR records and forward-confirmed reverse DNS for an IP address.
SPF Validator
Validate Sender Policy Framework (SPF) authentication of a DNS.
DKIM Validator
Validate a DKIM selector and public key record.
DMARC Lookup
Lookup DMARC records for the domain name in the DNS system.
MTA STS Lookup
Look up MTA-STS records and policy file details.
TLS RPT Lookup
Validate TLS-RPT records for email delivery reporting.
MX Validator
Validates and verifies email MX records to ensure proper mail server setup and reliable email delivery.
Suggest an improvement
Tell us if something is confusing, broken, incorrect, or missing. Feedback helps us improve the tools and workflows people use every day.